Re: Topband: 160 FT8
Yes, I can earn a 80m CW DXCC, 80m PHONE DXCC, 80m DIGITAL DXCC, BUT NOT 160M CW DXCC ! Whatever you call it, it is not right, not is no fair. PHONE I used my voice, CW I used my skills, FT* YOU used your PC. Who will be the first to claim # 300 on 160m FT*. No shame on that! 73;s N4IS -Original Message- From: Topband On Behalf Of Joe Subich, W4TV Sent: Monday, February 19, 2024 10:01 PM To: topband@contesting.com Subject: Re: Topband: 160 FT8 On 2/19/2024 9:30 PM, Tree wrote: > But I do disagree with that statement. You still used your ears with > SSB. Go back even further ... when Phone came along. Where was the skill in phone (compared to CW)? FT8 may be the modern Phone. 73, ... Joe, W4TV On 2/19/2024 9:30 PM, Tree wrote: > Agree that this is getting old. > > "Go back and research the transition from AM to SSB. It’s much the same." > > But I do disagree with that statement. You still used your ears with SSB. > > Tree N6TR > > On Mon, Feb 19, 2024 at 6:10 PM Cecil acuff wrote: > >> FT8 is here to stay….and there will be others! >> >> Go back and research the transition from AM to SSB. It’s much the same. >> Complain as you will….if you cling to CW as the only valid mode of >> communications on Top Band, you will fail. You are willing to >> sacrifice RTTY to FT8 just recently… in an effort to justify your >> position….to no avail. Technology moves forward….you stay behind. >> All modes are valid and there is nothing you can do to halt it. >> >> AM, SSB, CW, RTTY, Digital modes including FT8….all valid. Doesn’t >> matter if you used a bug or a laptop…all valid. >> >> Fight about remote ops…a much more productive fight!…..that’s if you >> must fight! >> >> This discussion is getting old…. >> >> Cecil >> K5DL >> >> _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: https://clublog.org/logsearch/CB0ZA
Just my 2 cents SSB, CW , Digital and Mixed modes is the standard for DXCC in all band, less 160m and VHF, I quite understand it for VHF. But 160m is considered an impossible band for most of ARRL God ! or second class... 73 N4IS JC -Original Message- From: Topband On Behalf Of Jim Brown Sent: Monday, February 19, 2024 7:02 PM To: topband@contesting.com Subject: Re: Topband: https://clublog.org/logsearch/CB0ZA On 2/19/2024 3:25 PM, Michael Tope wrote: > Since reclassifying 160 DXCC totals to exclude FT8 would be terribly > unfair to those who submitted FT8 confirmations toward DXCC in good > faith, it seems like a possible solution would be to add provisions > for a CW endorsement to the 160 meter DXCC award. If it were workable > administratively, it would provide a way for those who made the > majority of their DXCC contacts on CW to compare themselves with > others who have done similarly. It would also provide a way for those > who enjoy FT8 to compare their progress with others in the "unlimited" > category. Who knows, it might even encourage a resurgence of CW > activity, since that endorsement would carry a certain cache. Hi Mike, Since what modes like FT8, JT65, and FST4 do is compensate for the drastically added electronic noise. Using those modes today is roughly comparable to working CW 20+ years ago. I would support the endorsement you suggest ONLY to those QSOs made on CW after about 2010. 73, Jim K9YC _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: NCC-2 antenna pattern?
Let's agree to disagree. It is not. I can send you a long list of station around me, down here is Broward County , Fort Lauderdale FL, just mentioning a few friends Peter N8PR. Ron W4BP. Scott W4SO. We were around 120 to 150 worked countries on 160m back on 2004. The RX antennas was mainlining EWE.s EWE';s in phase, When I upgrade my tower form 80FT to 120FT, all my RX antennas stopping working. I took a hit and figure it out, I needed to detune the tower. At the same time I built a Vertical Waller Flag. In the first year I reach 200 and in few more years 250. All my local friends, here in the same location did not hear the weak signals like my station and they did not move up on the 160m DXCC, not even close to 170 countries on 160m. The average here is 150 countries worked on 150m for a good station. I am not the only one 160m DXer in Florida, most of them are still below 200 countries in 160 after 30 or 40 years in the band. All of us are in the same location. You can go to ARRL list and find 100's of station in Florida but only 3 above 300's on 160m. N4WW Austin is in the band for 50 years. Doug NX4D and I less than 15 years, All is Florida On 160m the MUF is always good, the signal always arrive, the issue is signal to noise ratio. A good RX antenna have a directivity of 10 to 12 db RDF, a TX vertical 5 to 6 db RDF, the difference is 5 to 6 db. I measured signal to noise for decades, for each 1 db improvement in RDF, you gain 2 db on signal to noise ratio, so a good vertical RX antenna can hear 10 db better than a TX antenna, the HWF because the polarization filter can hear 20 db better them my TX antenna. Signal to noise ratio in your station! That is the secret, You can work the weak signal your neighbor can not if your care about keep the patter clean on your RX antenna, not the RDF in the paper, the one in your back yard. YES, l you can reduce the noise on your own RX antenna, RDF is the key, but if you allow the TX antenna interact with your RX antenna, you are deteriorating the patter and never experience the RDF improvement , because the actual RDF is reduced. You end up hearing the reflected signal from your TX antenna into your RX antenna and no gain in signal to noise can be achieved. This is not because your location, it is because the way you assembly your station. If you want to try it, check my presentation on World Wide Radio Operators Foundation https://wwrof.org/webinar-archive/n4is-waller-flag-construction/ https://wwrof.org/webinar-archive/high-performance-rx-antennas-for-a-small-l ot/ High Performance RX Antennas for a Small Lot. It not just a concept it is a proved concept with practical results! Don't tell my neighbors that they are in a fantastic 160m location, Florida used to be a black hole for low bands, and still is a black hole for most of us, if you don't detune your TX antenna, and all others cables 30 FT or longer. 73's JC N4IS -Original Message- From: Topband On Behalf Of Jim Clymer Sent: Tuesday, December 19, 2023 7:58 AM To: n...@comcast.net Cc: Jim Brown ; topband Subject: Re: Topband: NCC-2 antenna pattern? Come on, JC... Even I know, YOU know what K9YC is talking about! After living in IN for 15 years, CA for 34 years, and VA for 10 years, with essentially the same station setup, over the long term, for success on TB, QTH is paramount. (detuned TX antennas notwithstanding) BTW: I like your initials! 73, Jim - WS6X On Mon, Dec 18, 2023, 9:26 PM wrote: > So you cannot detune a TX antenna in IL, just in Florida? > > JC > Archives: http://www.contesting.com/_topband - Topband Reflector > > > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: NCC-2 antenna pattern?
So you cannot detune a TX antenna in IL, just in Florida? JC Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: NCC-2 antenna pattern?
"Since I am on a 50 x 100 foot lot, it is impossible for me to separate my rx antennas from my tx antenna. " Hi Rob, my city lot backyard is 50x100 and I worked (CW only) 305 confirmed on 160m from 2006 to 2019, it is not easy but doable to detune your TX antenna. I use a wire skirt around my tower, making it a UNIPOLE, the skirt and the grounded tower works like a 1/4 wave stub, with a high impedance at the base. That way the TX antenna does not interact with the RX antenna. Distance is another like what you want, but 1 wave distance is not far enough ,and It is 525FT for 160m, Detune is not the impedance on the fed line, it is the impedance from the antenna to the ground. If you TX antenna is isolated from the ground a relay can isolate the antenna from the ground. Any cable longer than 30FT should be take care as well., including rotor cables. Doug NX4D lives in 1/5 acre and he worked #315 from 2003 to 2019,. So don't give up. topband is a fantastic band when you can hear the weak signals. 73's JC N4IS -Original Message- From: Topband On Behalf Of Rob Atkinson Sent: Monday, December 18, 2023 6:14 AM To: topband@contesting.com Subject: Re: Topband: NCC-2 antenna pattern? Since I am on a 50 x 100 foot lot, it is impossible for me to separate my rx antennas from my tx antenna. Of course on transmit, preamps and the NCC1 are deactivated, but even so, the NCC1 had internal relay chatter (there are around nine PC board mounted relays inside). Small RF chokes in series with the DC power line to the box eliminated the chatter. I may have added bypass caps inside it but I can't remember if I did that or not. But if so, that wasn't enough. The chokes did the trick. Merry Christmas Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: GM from Timor Leste
“ no beverage, no contacts”. I live in a city lot and worked 305 on 160m, starting 2006, and I hear 316 countries, Doug NX4D lives in a 1/5 acre and worked 314 on 160m, starting 2003. We have no beverage antennas! People only see what they want to see! 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Looking back 11 years ago on 160
Fellow top-banders Propagation on 160m is always good. The MUF is always well above 1.8 MHz, so the signal always get into your antenna. The key on 160 is how low is your noise! The attenuation is the main factor, if the arriving signal is above noise you can copy it. So,.. you really have work to do at your side. Perception is a dangerous thing! We only remember the good things, the good times. If you don't take notes every week about propagation you just don't have the complete picture to remember it. Last night, OK1CF was 579. 20 dB above noise floor, Roger you too very strong. Low attenuation equal great conditions. However people don't turn on the radio if some web "podcast it" Conditions is what it is today, now, when you turn on the radio. You can not work DX on the bast, it does not matter. The most important equipment I have in my station is a very comfortable arm chair! 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: KH8 Demand on TB
Hi George During solar maximum the 160m propagation is different, sometimes a long path surprise us, but every 28 days there are a couple of good nights with good propagation. We just never know, the best QSO of your life time could be any night on 160m, on any given month or any given year. 73;'s JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Poor Conditions
As my good friend George AA7JV used to say Noise I UP! I live is a city lot, 20 years ago it was in a rural area, now it is in the city, The man made noise is exponentially going up. In 2006 I bult a vertical WF with great directivity, FPL , our local power and light company did and does a great job fixing power light noise. I had a good time enjoying it, big problem was Plasma TV, but it is gone now replaced with new OLED or equivalent screens. 2010 I built a horizontal HWF, the idea was to use polarization as a filter, manmade noise propagates only vertically polarized. I can check my notes comparing both antennas and at the beguine their were even, after 5 more years the vertical WF become useless due the amount of manmade noise. Now, the main problem here are solar panels and EV. Electrical vehicles are very noise but not a problem on the, when the get home and the owner plug the charger into a big power supply the noise become an issue form 500kHz to 30 MHz, every 100 kHz there is a cluster of noise. 1800, 1900, 2000 etc.;. Two EV generate two clusters but close together, not exactly on topo of each other. Solar panel noise goes always after Sun Set. Another "thing" growing up is noise from indoor LED growing plants lamp. These are really a big problem here on 14 MHz and 3.5MHz. My point is the we need new solutions to fight noise. My horizontal HWF is at its limit here. Just polarization filter is not enough anymore , It was necessary to detune the tower holding the HWF. The HWF at 60 FT with a 43db gain preamp was generation s6 to s7 on the S-meter with 600 Hz BW CW. After detuning the tower the noise is now s0, with some switching noise that the NB can remove it. The keep with noise going up, we need to take some difficult actions to avoid common mode noise. Doing the same is not working anymore. This video was made for a friend to see the test of the HWF at 60FT , not a good production, but give the idea how it works. https://youtu.be/IyXXFkuPZZQ 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Poor Conditions
<> Roger, I am afraid I do not agree. I started on 160m back in 1972, my first DX was 1974, living in a city lot I reach DXCC only in 1994, yes 20 years to do it. I moved with my family to Florida in 1999 , and I started all over again as N4IS. I reach DXCC in 4 years and got motivated to fight QRM again on Top Band. 2006 I built my Big Vertical Waller Flag and 2010 my Horizontal WF. With a good receiving antenna I worked over 300 countries and heard 316 until 2019. ONLY IN 13 years window! In 2020 the activity dropped due the pandemic and it is not back to normal yet. It is just starting to bounce back. I am now at 306 confirmed on 160m ALL CW, no FT* here by my choice, not wrong with DIGITAL, but is not my like. Jan this year, I works Eddy XV1X, CW on 160m long path on 160m. Propagation on the last 20 years was the best we ever had before on 160m. The propagation is bad as the receiving noise you have at your place and limited by activity. The best and comprehensive explanation about Top Band propagation you can find here, at K9LA site ; NM7M's book titled "The Big Gun's Guide to Low-Band Propagation" is in the 160m link. >> https://www.k9la.us/NM7M_The_Big_Gun_s_Guide_to_Low-Band_Propagation.pdf Several ham with dedication to reduce noise and improve RX antennas did the same or better than me. NX4D Doug #315, Jon AA1K #329 and others too. FT* gives the impression you don't need a good RX antenna for any band and recent DX expedition is going on that direction, it is a pit. 160m is always tough and hard to work DX, that is why we love 160m. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Topband Digest, Vol 250, Issue 14
>>I heard absolutely nothing from the Caribbean which is unusual.<< The hurricane season ends November 15th, Check hurricane tammy >> https://www.wunderground.com/hurricane/atlantic/2023/hurricane-tammy 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: E51D and OHQP
<< Contrary to what you hear repeated on the bands year after year, what Jim said is *exactly* right! :-) >> I'll add that NVIS is rarely —if ever— useful for working DX on 160m. << I am sure we never going to learn 160m propagation, but we can learn the basic stuff. We can learn by example or by engineering it. I moved outside Sao Paulo back in 1986 (I was PY2DP), first time in an almost rural suburb area. I build a 160m dipole/inverted V with the apex 35 ft hung in one three. With 800 W, I experienced a pile up of JA's on 160m , JA is the antipode of SPaulo, the far you can go, few weeks later I run a pile up W4 W2, East Coast US on 160m CW. So, by experience, the best antenna is the one you have, and you can use. By engineering, You can check with any antenna modeling software. Any dipole has actually two different pattern, one vertical polarized pattern along the wire an another horizontal polarized pattern broadside with the wire. Use 3D to separate the two pattern using EZNEC. One line is green and another is red. So the dipole or inverted V performs as a vertical antenna along the wire, like any short vertical, but.. and here is the but. A vertical antenna is good for TX, and a horizontal antenna is good for RX, the two pattern are 90 degree apart, together they become a unidirectional antenna. Jim is 100% right on both subjects I mentioned above. We just seems not to care about the basic stuff anymore. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: We need better preamps for 160 because FT8 activity
Hi Folks I am following the conversation about LOG RX antennas, I understand the pain from a noise city lot on 160m. it is hard. I am using Waller Flag's vertical, since 2006, and horizontal since 2010, however vertical noise is so bad with new solar panels and EV charges , on top of LED lights, that I no longer have my Vertical WF, it is inefficient for a city lot. My HWF is working very well. The reason I started a new tread is what I noticed during the last DX season. The number of KW station on 1840 is growing exponentially. If you have 100 station with 1kW on a small portion of the band, it is equivalent a 100 KW single station. Imagine 500 station, 500KW, My HWF preamp is in use since 2010, my first QSO with my 6xBF981 preamp was XU7ACY, long path (160m CW), from the same city lot, not so noise as it is today. However now with the number of FT8 KW's, and most of them very bad linearity, with phase noise several KHz on each side, my old preamp IP3 is not strong enough as it used to be. I will be back to old NORTON's preamp on my station with new high Q front end. With all the power of 100's FT8 station at the same time, the consideration for a new RX antenna and new preamplifier is raising the bar on overall performance. Any new ideas on high performance preamps for 160m?? We will need it. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: 160M Conditions
Hi Peter Signals from Europe were not strong but I worked over 50 counties on the first night. Few days ago Eddy XV1X signal was very good "long path" really SSW-SSW, CW solid 559, and just yesterday morning several station on the east coast worked XV1X on FT8. JT1CO is active, BY, HL JA's, 3W1T. most of traditional contest stations with good signals too. I think conditions are normal however more CW from Europe than USA, that's was a surprise for me. 73' JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Bad 160m Conditions
Hi guys This kind of propagation is common on 160m for this part of the solar cycle, I'd taking notes about propagation since 2006, and 2012 to 2014, all notes are very bad propagation in January, like we are seeing now. However there was great DX along those years. DX expeditions are coming back and the fun with them. As Frank mentioned, nowadays the E layer blocks most of the signals on 160, but some times the same E layer have holes and create some ducts that can allow DX for long distances with very strong signals. That’s one of many reason 160m is unpredictable and we need to work very hard to get a new one. 73's N4IS JC _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Verticals on the beach
Well People believe on what they want to believe. The difference from close to the water and far from the water is zero, nada, don’t bother. 10 FT , 100 FT and 1000 FT is the same. The difference "in" the water is > + 10 db., This is based on real experience and not a simulation on computer, please search the list archives for vertical on the water. You will find priceless information about it. http://lists.contesting.com/archives/html/Topband/ A practical issue is the change in impedance that can be solved with a remote antenna tuner. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Small Loop does not receive weak signal on 160m BOUVET RX SPOILER
Wes I missed the second question. How a receiving antenna can help on your signal there. The RX antenna is good as the directivity or RDF. Based on my measurements and extensive experiments with the Waller Flag, for 1 db improve in RDF you can get 2db or more on signal to noise ratio aiming at the signal, plus de rejection on side and back nulls. You can check more about this on my webinar at WWROF https://wwrof.org/webinar-archive/high-performance-rx-antennas-for-a-small-lot/ I measured 2db over 100 tests or more, including using WSJT SN readings. It is a practical result, not just computer simulation. With a good RX antenna 11 to 12 dB RDF you can work 150 counties on 160 any 12 month period. I did it for 10 years. Using a Waller Flag, Doug NX4D, worked 314 on 160m from a 1/5 acre lot. All CW. I started with a vertical WF on 2003, and an Horizontal Waller Flag in 2010, the noise here in my city lot is very high now, and my Vertical Waller Flag is down because the HWF does not see the vertical manmade noise, so I have no noise on the HWF. I worked in the last 10 year close to 300 countries on 160m, only CW, and I am now at 305, however I heard over 320 countries down here in South Florida from a city lot. The VWF can dig signals on CW 10 db below noise and my HWF can dig 20 db bellow noise, when you compare with the TX antenna. I can measure that as well, with 2 instances on WSJT on my radio two identical receivers, a signal -20 SNR on the vertical shows a 0 db on the HWF. More information about the HWF here > https://wwrof.org/webinar-archive/n4is-waller-flag-construction/ You can download the presentation too, Doug and I do not provide any additional support or question anymore, we spent hundred of hours on it and few people listened us. So, conclusion a RX antenna can dig you signal out of the noise. 73's JC N4IS -Original Message- From: Topband On Behalf Of Wes Sent: Friday, December 23, 2022 9:45 PM To: topband@contesting.com Subject: Re: Topband: Small Loop does not receive weak signal on 160m BOUVET RX SPOILER All interesting. But let me ask (and standby for flames) what is wrong with them simply listening on the TX antenna? I know, I know, conventional wisdom says that you can't possibly work 160 DX without a separate RX antenna. I'll confess that I am a little pistol and will never be on the TB Honor Roll, but I got on the band just to add another DXCC band to my collection (now nine). I'm now at 144 confirmed, running just 500W and a 55' inverted-L on both TX and RX. Generally speaking I hear better that I get out. Looking at my chances of working 3Y the optimum time is their sunrise (~3:30Z) when I am in complete darkness and straight across the terminator. They will have the sunlit ocean to their rear and the S. American landmass toward me. Maybe someone can enlighten me, but I fail to see how a directional antenna will improve the SNR of my signal at their end. Wes N7WS On 12/23/2022 6:46 PM, JC wrote: > Hi topband lovers > > > > Some friends contact me with deep concerns about the next Bouvet DX > expedition receiver antenna called SALAD > > > > > <http://www.lz1aq.signacor.com/docs/active-wideband-directional-antenn > a.php> Salad antenna > > > > I understand the concerns, Bouvet on 160m is a lifetime opportunity for most > top-banders! > > > > When Doug NX4D, me N4IS and Dr Dallas started to try to understand the > limitation of the new Waller Flag, the first big question was; > > > > How small a loop antenna can be to receive weak signal on 160, or MW? > > > > Dr. Dallas Lankford III (SK), measured the internal noise of a small loop. > 15x15 FT on his quiet QTH, and wrote a paper with the derivation necessary to > calculate the thermal noise of a small loop. The study most important point > was: > > > > The sensitivity of small loop antennas can be limited by internally > generated thermal noise which is a characteristic of the loop itself. > Even amplifying the loop output with the lowest noise figure preamp > available may not improve the loop sensitivity if manmade noise drops > low enough > > > > The noise on Bouvet island will be very low, < -120 dBm at 500Hz, and for > sure the internal thermal noise of the prosed RX antenna will limit the > reception of weak signals on 160m, it may work on 80 and above, but for 160 > m, it will be a set up for failure. > > > > Why not a single, trustable beverage antenna over the ice or snow?? Or a > proved K9AY or a DHDL?? > > > > Below is the almost good transcript of the original pdf Flag Theory, for the > long answer. > > > > > > 73’s > > JC > > N4IS > > > > Flag Theory &
Re: Topband: Small Loop does not receive weak signal on 160m BOUVET RX SPOILER
Doug NX4D asked me to add his comments, Hey JC and Topbanders, This is meant as a suggestion, not a criticism. The reason I sounded an alarm to JC was the concern that the proposed SALAD/ LZ1AQ 160m receive loops by the upcoming Bouvet DXpedition/ 3Y0J are much too small for receiving weak signals on 160m. With the current poor 160m condx, it would be a shame for them to go to all this trouble and expense, then not be able to pull in medium to weaker sigs with the loops. I would suggest the loop(s) be at least 10 ft (3m) diameter. >From experience I found that my original WF with small phased loops could not >hear the weakest sigs others around me were hearing, due to being thermal >noise limited. The solution was to make the loops much larger, by which I >could then hear all sigs very well. 73/ NX4D _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Radials, EZNEC and far field
Hi Frank You wrote " . A vertical over a salt marsh or within about a wavelength of salt water will produce 6 dB or more of gain at low angles compared to a vertical with poorly conducting soil in its reflection zone " The assumption that "next to the water" is the same as "in the water" , is a not right. It is not the same ! I listen to George signal with vertical "in the water " and the 10 db difference in signal is real. Moving the antenna on the beach and you lose 10 db or even more on practice, not on paper. I see that on my S meter more than a dozen times. George has a vertical on his house in Miami, the ground plane is just a plate down the water. The vertical is made with fiberglass pole 18m high. My antenna is a full size vertical with a good radial system over the Everglade land, if I dig 2 Ft I have water from the Everglade underground river. George can run a pile up from Europe with 10W, I can keep up with him running legal limit power. We are talking about 160m only. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Dipole/remote tuner
Jake One very simple solution is a double inverted V. I built and used this antenna for several years. The SWR can be 1:1.5 or lower from 3.5 to 3.8 MHz. The basic principal is a double dipole spaced 4 to 6 ft, very fat. The impedance at the enter is 300 ohms, however if you make it an inverted "V", the feed impedance is 200 ohms. The tower can be at the center with two support 2 to 3 ft each side. This configuration makes easy to hung a large 4:1 BALUN on the feed point. I recommend the BALUN with material #2 T300B or T400B with Teflon isolated wire, T200 is too small. Adjust the antenna to min SWR around 3.65 MHz. With a good BALUN the SWR would be very low, 1:1,05 is very achievable. I like a good quality RG-213. To keep the wires moving with the wind I used two 1/2 white PVC tune and a 3/4 at the end, on each side. You may not need a tuner at all. 73 JC N4IS -Original Message- From: Topband On Behalf Of jcjacobsen via Topband Sent: Saturday, November 12, 2022 11:08 AM To: topband@contesting.com Subject: Re: Topband: Dipole/remote tuner Looking for input from the collective knowledge of the reflector. You have a wire dipole for 75 meters fed with a 1:1/5K rated balun. You want to transition to a remote tuner so you can move around 75/80 meters. The question is: Do you leave the balun in place, or remove it and feed the dipole directly from the remote tuner? We have mixed answers from the local "Population". That's why I'm coming to the reflector. Please, don't be critical and ask questions like: what gauge wire, bare of covered wire, How high, yada yada yada, That's all. Thanks in advance. 73 K9WN Jake _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: J28MD, conditions
"The WSJT Modes, including FT8 and FT4, require a live operator" I am sorry to disagree, any "ROBOT" that you can buy on e-Bay, with your call sign, for $25 make the human operator 100% optional. Several DX entity become a cash cow for FT8 QSO/QSL confirmation money. Lots of reports of station 24/7 on FT8 for month. Just ask Joe. JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Series LC to notch AM broadcast ?
>>HP filters offer little rejection towards the top end of the AM broadcast band. like 1200-1710 khz. << I built several HP filters with >40 db attenuation on 1.7 KHz based on QST, I don't remember the year 90's about it. But some good information here > https://www.qsl.net/wb5wpa/Filter/DesignAMBrickWall_08.pdf You can but a 200W HP at DXE, this filter is the best you can get and very well calibrated/built. https://www.dxengineering.com/parts/dlw-fl1718 73' N4IS JoseCarlos _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: K9AY Loop Questions
Hi Don That's a very interesting question. The K9AY is ground dependent. The reason is simple, the Loaded loop of flag has a resistor in one side and the transformer on the other side. If you want to make it reversible you need two relays, one on each end of the loop. What K9AY did was genius, he created a transmission line between the horizontal wire and the ground. Keeping the horizontal wire close to the ground it does work as a transmission line and you can move the resistor and transformer close at the center of the wire. With the resistor and the transformer closed to the center you can use just one relay to reverse direction. The switching for 4 direction became easy to implement. The horizontal wire must be close to the ground, is you raise the ends of the K9AY the impedance of the transmission line also raise and deteriorate the SWR on the loop, deteriorating the pattern as well. Same on the SAL the ground is part of the antenna. Very different of the Flag and WF that is ground independent. You can install a flag or WF at 50 FT high and pattern will be the same , not the case of the SAL or K9AY. Not because the loop, but because the transmission line that allows you to move the resistor and the transformer close to the center of the antenna. The SAL is the same, the two transformers 1:X loaded the wire as a resistor and a transformer, there is no magic about that, electrically it is a resistor load and a transformer, changing the name of the device does not change how it works. You cannot install the SAL far from the ground, it does not work, the same way the K9AY does not work far from the ground. 73's JC N4IS -Original Message- From: Topband On Behalf Of Don Kirk Sent: Friday, January 7, 2022 12:15 AM To: Jose_Carlos Cc: W0MU Mike Fatchett ; topband Subject: Re: Topband: K9AY Loop Questions Hi Jose, To keep things simple, I say the K9AY is not like a pennant or flag since it has been demonstrated by many people to be more ground dependent (sometimes needing added ground radials). Under certain conditions the K9AY should be identical to a Flag or Pennant but since ground radials have been shown to drastically impact the K9AY performance depending on the ground conditions this sure does not sound like this is always the case. I won't debate the SAL (Shared Apex Loop), other than to say from a construction standpoint it's definitely not the same as the K9AY or other EWE type antenna (Flag, Pennants, etc.), and modeling the SAL definitely yields a different pattern than a single pennant or flag when used in the "in line direction" but as you said modeling does not always reflect reality (your example was EZNEC not doing a good job with loops close to ground). I have never used an SAL and therefore my statements are only based on what modeling yields, but to say the SAL is the same as a K9AY is hard to believe regardless if it performs better or worse than the K9AY, just based on the design. P.S. I believe there is a newer version of the SAL in which the two halves of the SAL share the same center vertical conductor, but again I'm not making any claims about the design. Also note I'm using 4NEC2 for my modeling, not that it necessarily impacts my above statements. 73, Don (wd8dsb) On Thu, Jan 6, 2022 at 10:27 PM Jose_Carlos wrote: > Don > > I’m afraid your information is not accurate, SAL is the same as a > K9AY, the two wires close to each other can be removed because they > cancel each other. The remain wires works like two vertical in phase, > as the same in any flag, loaded loop or pennant. The cardioid pattern is the > same. > > The is no implementation of two SAL in phase because it does not work, > the phasing system is too complex to phase two SAL. > > If you know the people that actually tested the antenna, you know that > the claimed RDF was never achieved. > > The RDF of the K9AY is the same of the SAL, the EZENEC does a horrible > job with loops close to the ground. > > Saying that, both antennas are excellent receiver antennas if you > don’t have anything else. > > 73’s > JC > N4IS > > Sent from Mail for Windows > > From: Don Kirk > Sent: Thursday, January 6, 2022 7:19 PM > To: W0MU Mike Fatchett > Cc: topband > Subject: Re: Topband: K9AY Loop Questions > > Hi Mike and gang, > > It has been a long time since I looked at the SAL in which I modeled > it with the help of the designer of the SAL (KB7GF). The SAL is > actually different than the K9AY and other EWE types of RX antennas > which have a typical RDF value of around 7.8 because the SAL (Shared > Apex Loop) antenna actively uses two of its loops which are "in line" > with each other for what you might call the primary direction > (direction in line with the loops), and these two ph
Re: Topband: K9AY Loop Questions
Hi Andrew He concept is very simple, you can phase 2 verticals. 3 verticals or 4 vertical. See you got, two verticals in phase give you a cardioid pattern, only one deep null on the back. Moving to 3 or 4 verticals gives you two deep side nulls plus some front back. The SAL does not have side lobe nulls. The feed system does no change the fact that you have only two vertical wires as antenna, the inclined wire can be describe as two vectors one vertical and another horizontal. The two vertical vector and the center of the inclined wire define the pattern. See the case of a DHDL, invented by George AA7JV, the vertical wires are far apart and the two inclined wires vertical vectors are half way each other. The DHDL has 4 verticals as the Waller Flag with two independent loops making 4 verticals as well, but the gain of the DHDL is 1-2 db below the WF. Why? the reflection between the two loops and the proximity of the two vertical vectors impact the DHDL pattern, as well the two verticals wires on the SAL. The SAL and the DHDL does not have side lobe nulls. One Loaded loop or EWE, K9AY RDF is close to 9 db, the SAL and DHDL are slighted better RDF 10 db on EZENEC, but again on practice, measuring the diagram of irradiation the SAL never achieved the extra 1 db in RDF. Two loaded loops has side lobe nulls and RDF is close to 12 db, very similar to 3 element yagi azimuth diagram. Both antennas, the SAL and the K9AY have impressive deep null on the back, giving you a good front back. It is a null on the back , very different than front rear, that take the 180 degree energy between the front and the back. You can find several stations using two DHDL in phase and it does work, but you wont find any array of two SAL because the phase is so critical that became impractical. 73's JC N4IS 73 Andrew Ikin G8LUG _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Great Engineering by AA7JV
You guys have no idea how many, not hours., days not month .. years of hard work George put in this project. It is a huge invention , a frontend to RX/TX CW 1824 and RXTX FT8 on 1840 at the same time using one TX antenna one KW amplifier and two radios. The RIB is not a plug and play unit, it needs to be installed, connected adjusted, erect antennas, all tasks like a regular DX expedition. Refuel every hour. Etc. What it's save is people on the island, eating , sleeping, etc , the operators can stay on the boat or in the island,. Don't expect a dish with broadband internet to allow an intercontinental remote operation. RIB is not an appliance. People risk their lives on small boats every day landing to operate the radios. Think about it. RIB is very far from a remote station. It is a remote control limited to 900 MHz link and few miles away in the ocean. Try to make the boat stay put and not moving to aim the 900 MHz yagi from the boat to land. That is one of George's finest invention. Thank you so much George. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Screening Effect of Trees
Hi Roger That is a very important question and the answer may surprise a lot of folks on Topband. Kay KE4PT worked several years on Motorola simulation RF in hollow bodies for pagers and handheld close to the human body Kai Siwiak KE4PT, QEX Editor. Kay prepared this presentation for our local DX club. https://qsl.net/k4fk/presentations/2018-May-02-KE4PT-LiveTrees-SFDXA.pdf A Dipole 0.2 Wavelengths from a Tree looks like a 2-element Yagi on 30 MHz. on 160m the F/B only 1 db. Regards JC N4IS -Original Message- From: Topband On Behalf Of Roger Kennedy Sent: Saturday, April 3, 2021 2:08 PM To: topband@contesting.com Subject: Topband: Screening Effect of Trees There always seem to be a lot of discussions on here about Antennas . . . so thought I'd start a new one. I've never seen any definitive figures for it . . . but I've always felt that any antenna with lots of trees around - especially Verticals, where the current maximum is near the ground - is BOUND to suffer a certain amount of radiation loss, simply due to the screening effect of those damp trees. I've certainly always noticed that any antenna wire that goes near any tree affects the resonance quite substantially. A lot of people refer to proper Field Strength tests carried out by Medium Wave broadcast engineers when talking about 160m Vertical Antennas . . . but I doubt if any have of them had their antennas anywhere near any trees, so can't offer any figures for their effect. I've also always been pretty sceptical about the accuracy of the various Computer Modelling programmes when it comes to 160m antennas . . . particularly as it can't properly predict what is happening regarding the ground with horizontal antennas that are very low in wavelength terms (and I mean Ground, not Radials) . . . but equally, I don't see how it can properly predict the effect of trees (or various buildings, for that matter) Roger G3YRO _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Portable transmit antenna suggestions?
Hi Luke The best signal ever on 160m from that part of the world was possible and only possible with the vertical IN the salt water. The radials making electrical contact with the water. Pleas talk with George, he developed a simple vertical in U shape ., good for 80m and 160m, he used it in Chesterfield. > http://www.tx3a.com/ Whatever you do , even 43FT ( 12m) high like the one George used on KH1 will work very well IN the water , not close to the water, or near the water. 73's JC N4IS -Original Message- From: Topband On Behalf Of List Mail Sent: Wednesday, March 10, 2021 6:38 PM To: Rodman, David ; topband@contesting.com Subject: Re: Topband: Portable transmit antenna suggestions? I’m also interested to follow this discussion, as I’ll be activating two VK9 entities later this year. My experience is with Inverted-L antenna, on Norfolk Island we used a big Norfolk Island Pine tree for support, and Mellish Reef an 18 m SpiderPole, which both worked well. 73, Luke VK3HJ Sent from Mail for Windows 10 From: Rodman, David Sent: Wednesday, 10 March 2021 10:37 PM To: topband@contesting.com Subject: Topband: Portable transmit antenna suggestions? My group is planning a Caribbean trip next year for one of the CW contests. If anyone has some ideas on design or deployment of temporary antennas for DX (160m or any low band actually), it would be helpful as we are in early planning. If you have done this before, luggage is the preferred method to bring on the trip. Please feel free to comment directly to me if you feel that bandwidth is not appropriate for this group. Thanks. (rodmanatbuffalodotedu) --- David J Rodman MD Assistant Clinical Professor Department of Ophthalmology SUNY/Buffalo Office 716-857-8654 _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Usable size of Flag antenna and FSM
Hi Eric Congratulations, wow!! Great work. 73's JC N4IS -Original Message- From: Topband On Behalf Of Eric NO3M Sent: Friday, February 26, 2021 6:44 PM To: topband@contesting.com Subject: Re: Topband: Usable size of Flag antenna and FSM Anti-phased double loops are also a good way to approach an RDF of 10dB on 2200m (137kHz). 1/2lambda is nearly 3600ft so broadside arrays and beverages are usually a non-starter... close spaced end-fire vertical arrays get very touchy (amplitude/phase). A DHDL style system spanning about 350ft works well here (quiet rural QTH): http://no3m.net/2020/09/2200m-double-loop-receive-antenna/ The one I use is aimed west and hears VK4YB (and recently VK2AN) on 2200m most mornings starting a couple of hours prior to sunrise (and at times has gone an hour or more past sunrise). - Eric NO3M On 2/26/21 12:57 PM, n...@comcast.net wrote: > I would like to share some of my experience with small flags'. > > > > The directivity is the same for a large chance in frequency but the gain > increase with size. > > So a small loop is not thermal noise limited on 160m, and works very > well on > > 80, 60 40 and 30m. _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Usable size of Flag antenna and FSM
I would like to share some of my experience with small flags'. The directivity is the same for a large chance in frequency but the gain increase with size. As a reference NX4D started with a single flag 14' high 7' wide , using a 20 db gain preamp. Is was good enough to work 150 countries on 160m, for 80m you can reduce the size by 1/2 and expect the same results. Basically it is a flag like k9AY, EWE, pennant and others loaded loop, one resistor and one transformer. The RDF is a limitation and Doug phased two loops 14x7 spaced 16ft for a total boom of 30FT. all fiberglass, and an isolated mast from the tower and, not portable, I called small Waller Flag. The two 14x7 flag was good enough to work over 200 countries from a 1/5 acre lot in a subdivision with a lot of noise form neighbors. Detuning the TX antenna was a must for good performance, including working JT1CO direct path over the North pole on 160m. But the gain of the antenna was a limitation on 160m, and he built a Monster WF to work 311 DXCC on 160. 2 db NF and 20 db gain is all you need for a vertical flag or dual flag like the WF(Waller Flag, from Doug Waller, NX4D) 33db gain is too much for a flag or WF vertical, it is good for a flag or a WF horizontal, and at least 75 ft above ground. Here is important to remember if you S meter is moving you have too much gain, I match my preamp gain for s0 on band noise during the day. There is a lot of signals bellow S0. Keep the gain at minimum. To reduce common mode noise a twisted pair 100ohms feed like helps a lot. Measure noise figure at 1.8 MHz is a great task and care, with a good signal generator and good sound card, you can take one measure in 2 hours of work for -+ 0.1 db accuracy. Doug me and Dr Dallas did a long experiment to measure that and a small flag 14'x7', was not thermal noise limited for DX use on low babnds. At a very quiet rural area with -125 dbm noise floor during the day. For reference , my city lot average -85 dbm during the day and the best I ever measured was -95db on those winter Sunday Mornings with light rain. The Dallas files is not available, Dr Dallas is SK but I have some paper I can share here. So a small loop is not thermal noise limited on 160m, and works very well on 80, 60 40 and 30m. some big contest station using a HWF reported problems of power line noise on 20m and the HWF saved them transmitting on the yagis and receiving on the HWF. On 80 and 40m the HWF is comparable only to a 4 elements full size yagi. ( same directivity, but vertical noise canceling) The easy way and accurate is to use FSM easy to do in 3 steps , here >>> https://www.owenduffy.net/software/fsm/index.htm FSM (for Field Strength Meter) is a software application that extends a conventional SSB receiver to allow measurement and calculation of field strength of radio signals or interference. FSM is a software implementation of a development of the technique described by Ed Hare of the ARRL in "Manual Testing of Field-Strength Levels Using Conventional Receivers" dated August 2004 . You need a good sound car and a 50 ohm shielded load, like an N or BNC connector 50 ohm termination. Regards JC N4IS Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Understanding or attempt to understand a flag antenna
Hi Guys This concept is important and very confusing, so sorry for being a broken record. Ill keep it very simple to understand. The Flag antenna and its variances, EWE, pennant WF SAL DHL and others nice names are basic the same and like this: Two wires in U shape, one upside down and one normal , with two openings. _ || || || Open1open 2 || || || The way to see it is like two vertical dipoles and two horizontal phasing lines. On the opening one we terminate with a RESISTOR, the valuer of the resistor is not important but for this exercise lets use 1000 ohms. Or two vertical vectors and two horizontal vectors. O the opening one we will connect the feed line. Thats the Flag, two vertical in phase, Because the vertical dipole is too small it reflects the current to the other dipole., and vice versa. The side one with the resistor the current will be dissipated on the resistor,, but on the open 2 the current can me connected to the feed line. At this point the system could be balanced and the reactive component will be very low if we pick for the feed line the same impedance of the load, 1000 ohms. You can simulate that on EZNEC and you will find it very broadband. The 1000 ohms feed line is part or the receiving system and not part of the antenna, so any loss will represent noise and will be add to the noise figure of the receiver,. It you use a 9:1 transformer, the feed line could be close to 100 ohm, It is simple to use a twisted pair close to 100 ohm impedance , like twisted pair form a Ethernet cable will provide very low SWR and no common mode noise, no shield is necessary. The losses on the transformer and the feed like is part of the receiver input circuit and not part of the antenna. The power noise is independent of the valor of the resistor and the noise temperature on the vertical dipole open 2 is the same as any dipole. Please keep it simple and G/T of a dipole is very well know. It is just two phased very small dipoles. Based on the above is very simple to understand the EWE, just replace the normal U by the antenna reflected by the ground (like a mirror). Cut all by ½, so the resistor will be 500 ohms and the impedance easy to match 50 ohms using a 9:1 BALUN Also the K9AY is easy to understand, just think the ground as a 1000 ohms transmission line, and you can move the resistor close to the BALUN, like the EWE. As any antenna, the thermal noise is the limit of the amplifier to produce any gain, if you want to work over 300 DXCC ( confirmed ) on 160m, make the flag 24x 12 and use it, spend time on that chair , tunning the radio and enjoying 160, it is not easy and thats why we love it. 73 JC N4IS _ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Receiver Equivalent Noise Bandwidth
Here the procedure I used to measure my receiver equivalent bandwith to calculate NF. https://www.owenduffy.net/measurement/enb/MeasureIfBw.htm SpecrunLab is also a very good tool to measure EBW https://www.owenduffy.net/measurement/enb/MeasureIfBw2.htm JC N4IS 73's _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: The WD8DSB mini-flag antenna
>> 1. I am specifically talking about "small" loops. The antenna in question is not a "loop" it is a terminated loop, the diagram is a cardioid, it is very broadband 1-10, like 1 MHz to 10 MHz or 3 o 30 MHz with the same irradiation diagram. The behavior is comparable a two dipoles in phase. Thermal noise is low as the resistor. >> 2. In small loops, the ohmic dissipation of the conductor vastly overwhelms >> the tiny radiation resistance. Yes , but loads loop is based on reflected wave and the one direction current dissipate on a 1K resistor ( gives you the front back and the other direction the current see a 9:1 Balun. Again it is not a loop the Q is very very low because it is broadband, >> 3. This is unlike a vertical antenna or a dipole, which can be considered >> non-dissipative. Again it is not a loop with high current and high Q or a tunned loop, it is very broad band the BW is over 10 MHz. >> 4. Therefore, if the conductor is at a physical temperature of 300K, its >> Johnson noise will correspond to that temperature. The voltage is not over the wire in on the termination due the high SWR, one side is dissipated, the one you don’t use and the other is a transformer. >> 7. It is extremely easy to get a 50 ohm NF of 0.5 dB with a BF981 at 88 MHz >> as specified by its data sheet. All you have to do is transform the 50 ohm >> source so that it loads the FET with about 1,000 ohms. I did this 40 years >> ago. Unfortunately, at 1.8 MHz, the flicker noise of the BF981 dominates, >> so you can't get the low NF down there. >> 8. I did this same experiment with the multiple paralleled BF981's over 15 years ago and was limited by flicker noise, which is unspecified, YMMV. Maybe you had better devices than I did. > pair of phase loops. A/B tests with NORTON preamps show not possible > to copy the weak signals I did copy with my 6xBF981. Here I agree, I was luck , I was not expecting 43 db gain. I was looking for a good input filter and I used a T240-6 with litz wire for a Q over 500. The impedance of a 3T to 11T inductor and a very high Q provide a voltage gain at eh input , the transconductance of the gates doe the work and I got a 43 db gain single stage preamplifier with a very high IP3, the BW just enough for 40 Khz, but the extra gain make the preamp usable for 1.8 to 1.9 mHz. >> Considering that the input of the preamp is deliberately connected to the >> antenna, it is hard to imagine what signal the shield is shielding the >> amplifier from. Large BCB signals out of band coming up the feedline? Is >> the shield still needed for QTHs that have no nearby BCB stations? Not at all, the amp is very well protected below my desk, inside a galvanized steel box, inside an aluminum box and the preamp inside a tinplate box. My HWF a phase pair or loaded loops, reject vertical noise with a 50 db null at the direction of the maximum horizontal gain. Adding a negative gain over 40 db, the rejection of any vertical signal is over 90 db, no manmade noise or BCB in below the MDS of my system. All my cables run inside metal conduit too. The transmit vertical is a folded UNIPOLE and I use the skirt to detune the TX antenna during RX. You can find all information on WWROF webinar archive. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: The WD8DSB mini-flag antenna
Hi Rich " The problem here is that any loop antenna inherently has a noise temperature of 300K, because it is lossy, and because it "sees" the earth" Would you elaborate on that? Small loop 1/10 of wave length works very different from a loop or large loop. I experimented with a large number of small loops in phase on 1.8 MHz. The frequency is very important because almost everything we know is different around 1.8 Mhz. Local noise is the most misunderstood figure. On top-band during a winter Sunday morning the noise can be low as 70K. On topband the only source of nom mam made noise atmospheric noise. No atmospheric activity means no noise. Yes it is that low. I am using horizontal phased loops for almost 15 years. It needs to be high for 160m, my is at 120 FT, it is large 50 Ft boom and loops are 24 x 12, all fiberglass. The gain is around -53db. The preamplifier required a minimum sensitivity is near 1 db NF, for that winter Sunday morning on 160m. I tested almost all available preamplifier, and the NF at 1.8 MHz is very different from NF measured at 10 MHz. The best I found was the NORTON with 1.5 to 2 db NF. I developed my own preamplifier , the same I build in 2010 still in use here, using 6 BF981 and large Q input filter. It measured .7 db NF including the input tuning filter loss. It does make a difference on signals at noise level. I built one for NX4D and Doug still use it. Making it short, I heard 316 countries (CW) and worked 305 since I built my N4IS preamp on 0ct 2010 (city lot). Doug worked 311 from a 1/5 acre lot using a pair of phase loops. A/B tests with NORTON preamps show not possible to copy the weak signals I did copy with my 6xBF981. Implementation is a different ball game. The .7 db NF preamp needs 3 level of shield including a magnetic shield with steel, just aluminum is not enough, and no open shield at all, a 1 mm gap will ruin your system. You can find information about my preamp on google or WWROF archives. A friend told my 2010 seems to be a very long time ago. Sure It does. 73's N4IS JC -Original Message- From: Topband On Behalf Of Richard (Rick) Karlquist Sent: Wednesday, February 24, 2021 12:50 PM To: GEORGE WALLNER ; Don Kirk ; topband@contesting.com Subject: Re: Topband: The WD8DSB mini-flag antenna On 2/24/2021 6:32 AM, GEORGE WALLNER wrote: > Don, > I put that note out because friends were asking if with a > "ultra-low-noise" pre-amp they could use it for DX. Unfortunately, > that's not the case. (I have tried.) George, AA7JV/C6AGU > The problem here is that any loop antenna inherently has a noise temperature of 300K, because it is lossy, and because it "sees" the earth. Therefore, a 0.5 dB NF amplifier adds 0.5 dB of noise, etc. As opposed to the 0.5 dB NF amplifier on an EME array that is something like 10 dB better than a 3 dB NF amplifier because of how noise temperature works. Also, for NF's below 3 dB or so, the source impedance is very critical in order to actually achieve the specified NF. This is impossible in an untuned wide band loop antenna. So in practice, a NF of around 3 dB is the best you can do, and even that may be optimistic. BTW, the multiple turns on the loop do not increase the available received power or SNR in any way. They simply increase the source impedance. It is analogous to a folded dipole. There are two tools that will reliably increase sensitivity: 1. Make the loop area larger. 2. Change to a tuned loop. 73 Rick N6RK _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Topband Digest, Vol 192, Issue 33
really two verticals, the two vertical wire in the center works like a transmission like the almost cancel it self, it depending on the adjust of the load, The BALUN with 1 turn primary impedance depend on the impedance ratio, lets say 9:1, a 100 ohms load represent a 900 ohms impedance on the secondary. This load thing is complicated but it works and the cardioid patter is there, and very similar to a Flag. Same variation in phasing system like DHDL , has some improvident on RDF but is not like a 4 vertical because the two inclined wire 180 degree out of phase cancel it self. There is a .5 or 1 db increase on RDF depending on the quality of the ground, The DHDL works better on good ground like near the beach. Same reason the K9AY the horizonal wire is a transmission line with the ground. The SAL vectoral components are very similar to a DHDL. It is .5 db better than the single FLAG. But enough to give you around 2 db increase on SNR. My webinar is available on the WWROF archives, both presentation are there with the slides in pdf with more complete explanation. The presentation is a result of 12 years if experiments and data collected on thousands of measures, limited by my owl resources. It is a start point for more developments, just a ham contribution with our ham spirit. 73's JC N4IS -Original Message- From: Topband On Behalf Of daraym...@iowatelecom.net Sent: Saturday, December 29, 2018 1:13 AM To: topband@contesting.com; W7RH Subject: Re: Topband: Topband Digest, Vol 192, Issue 33 I can heartily confirm Bob's experience. I live in Iowa and moved from the suburbs of Des Moines to a rural setting 22 years ago. I have a well constructed overhead single phase 13.2 kV distribution feed on the road 1/4 mile from my home. My house is fed underground from the pole to the transformer and underground from there to the house. When I first moved here my mid-day noise floor on a 1/4 wave vertical antenna ran around -125 to -130 dbm (300 hz bandwidth). Switching from no antenna to the 1/4 wave vertical on a sunny mid-day made a obvious but fairly insignificant difference. I had very little man made noise. I then added a four square transmit array. I subsequently put up several single wire Beverages, two-wire reversible Beverages, and was the first to build W8JI's passive/tuned vertical array design (which, oddly enough, had a simple design error which Tom quickly caught and corrected). While all the RX antennas worked, they rarely out "heard" the four square TX array and if they did, not by much. Remarkably, they didn't "out hear" the 1/4 vertical by a whole lot many times either. I began wondering if all these RX antennas were somehow defective (it's kind of hard to screw up a Beverage). The answer proved out to be. . .they were all working fine. I have mentioned this a couple of times over the years but perhaps it's worth noting. The bottom line is. . .if you have a really quiet QTH (getting to a rarity), having a terrific RDF doesn't buy you much in terms of improving real S/N performance (with no "N" ?) and true ability to hear. If you are fortunate enough to be in this situation, you also quickly realize quiet low gain RX antennas are often noise figure limited (on several occasions people kept telling me "you just need more gain". . not necessarily so). About six or eight years ago I put up an early Hi-Z 8 circle array which has and continues to perform extremely well. Interestingly enough, many times it doesn't hear all that much better than the four square TX antenna (but putting it in diversity is a huge help). That said, with all the encroaching rural homesteads being built with a mile or two, my noise floor over the past five years or so has slowly crept up to about -115 or -120 dbm. Sometimes I'm seeing -115. Lee/K7JTR understands the low noise floor issue very well and, at my and others behest, developed the +6 amps for the Hi-Z antennas with improved NF. He and I have had discussions about improving this further but, frankly, I'm not certain there is much of a market for people with true -130 noise floors. . .hi. With my ever increasing noise floor, the performance difference between the Hi-Z 8 and the TX antenna has become more apparent. Sadly, my quiet QTH is not as quiet as it once was making RDF now matter more. See you all in the Stew. 73 and Happy New Year to all. . .Dave, W0FLS -Original Message- From: W7RH Sent: Friday, December 28, 2018 11:04 PM To: topband@contesting.com Subject: Re: Topband: Topband Digest, Vol 192, Issue 33 All, Two cents worth of comments on thread. The SAL, K9AY and Waller Flags all work well and have their limitations. They do help the city folk improve the ability to receive. The WF works great if you can get it up in the air and rotate it. That is if you can keep it there in one piece though snow , ice and wind. It al
Re: Topband: Topband Digest, Vol 192, Issue 33
Jay The SAL is only one electrical equivalent loop with 9 db RDF, the Waller Flag has 2 flags in phase with 11.5 db RDF. It is not on the same class. Sorry but I am been honest here, both antennas need the tower to be detuned to work. The invention of a BALUN just transfer the impedance replacing a resistor 1000 ohms to load the loop as any FLAG, the other BALUN you call a special name to patent, it is just a simple BALUN, it is just the feed line , the SAL does have one resistor and one feed point, the two vertical wires works like a very short transmission line. And it removed does not affect anything, You own engineer admitted that. To prove that it is no the same class, check the side null, two flags can provide a deep null on each side , 30 db , and 20 db F/B. Does your SAL provide side null, 82 degree front lob,. 11.5 db RDF and it is ground independent? NO. Can you elevate it and turn.it? NO The SAL is grounded dependent and can not be elevated and turned.. Sorry the SAL is identical a K9AY, build them side by side and you will see it. The HWF is at another level because cancel manmade noise and the increase on signal to noise ratio improvement is 20 db or better. You get what you pay for. I can tell you that the SAL is really a Snake Oil. Work 300 countries with a SAL and I will give you some credit. 73. JC -Original Message- From: Topband On Behalf Of Jay Terleski Sent: Friday, December 28, 2018 12:20 PM To: topband@contesting.com Subject: Re: Topband: Topband Digest, Vol 192, Issue 33 JC said, The SAL is a good antenna, any directivity increases signal to noise ratio. The RDF is 2 to 3 bd better than the vertical antenna, it means the improvement on signal to noise ratio is about 6db. You can dig signals 6 db below noise with the SAL that you cannot hear with the inverted L. > > ..but the SAL has the same performance of a K9AY, or EWE or a single FLAG, The clamed 10 db RDF was never confirmed or measured, The SAL is the most complicated K9AY you can build. The separation in two loops does not change the directivity. > > You can phase 2 FLAGS to increase RDF to 11.5 DB, as well you can > phase two K9AY or 4 if you want, but the SAL phasing system is complicated and it is impractical to phase two SAL to increase RDF. > > 73 > JC > N4IS JC the SAL is not in the class of the single terminated loops of the K9AY antenna, and you of all people should know this as it is in the same class as your waller loop in that it uses two loops do derive the pattern. in each of the 4 directions. And combines the loops to get the intermediate directivity in 8 directions. It is a fantastice ground independent antenna and we can't hardly keep them in stock. As to your claim that the RDF has not been confirmed is also wrong. It has been run on many simulation platforms and I am sure you have studied it well. We have a Yahoo group that you may join and get the NEC models and you may feel free to join it as well. The SAL is a fantastic antenna, and if one takes time to optimize it, it will give the performance you see on the videos on You Tube, etc. It doesn't suffer from huge low gain problems of the HWF you sell, and is much more cost effective for the small guys to get a good low band antenna working to share DXing on top band as well as others as it is very broad banded. Due to it's gain, we do not need exotic amplification the the HWF requires. And we publish the details so a customer may build their own successfully. Try the SAL-30/20/12 guys, I have two of them up now and plan to phase them, as one of my customers has done. Thanks for reading and Happy New Year to the group. Jay, WX0B Jay Terleski Array Solutions 214 954 7140 On Fri, Dec 28, 2018 at 11:00 AM wrote: > Send Topband mailing list submissions to > topband@contesting.com > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.contesting.com/mailman/listinfo/topband > or, via email, send a message with subject or body 'help' to > topband-requ...@contesting.com > > You can reach the person managing the list at > topband-ow...@contesting.com > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Topband digest..." > > > Today's Topics: > >1. Re: Inverted L improvement question (Cecil Acuff) > > > -- > > Message: 1 > Date: Fri, 28 Dec 2018 10:31:56 -0600 > From: Cecil Acuff > To: n...@n4is.com > Cc: Wes Stewart ,Arthur Delibert > , Jeff Woods , topband > > Subject: Re: Topband: Inverted L improvement question > Message-ID: <592429b6-a654-473e-88e6-62ebbf643...@cableone.net> > Content-Type: text/plain; charset=utf-8 > > I would
Re: Topband: Inverted L improvement question
Wes you're right The SAL is a good antenna, any directivity increases signal to noise ratio. The RDF is 2 to 3 bd better than the vertical antenna, it means the improvement on signal to noise ratio is about 6db. You can dig signals 6 db below noise with the SAL that you cannot hear with the inverted L. ..but the SAL has the same performance of a K9AY, or EWE or a single FLAG, The clamed 10 db RDF was never confirmed or measured, The SAL is the most complicated K9AY you can build. The separation in two loops does not change the directivity. You can phase 2 FLAGS to increase RDF to 11.5 DB, as well you can phase two K9AY or 4 if you want, but the SAL phasing system is complicated and it is impractical to phase two SAL to increase RDF. 73 JC N4IS -Original Message- From: Topband On Behalf Of Wes Stewart Sent: Friday, December 28, 2018 10:50 AM To: Arthur Delibert ; Jeff Woods Cc: topband Subject: Re: Topband: Inverted L improvement question I was an early participant in the SAL yahoo group and introduced Dan, AC6LA, to the group. He has provided a lot of modeling tools. That said, I lost interest after feeling that the design was too complicated, not well understood and suffered from a dizzying number of changes. I could be totally wrong about this, but that was my assessment some time ago and frankly I haven't kept up. Wes N7WS On 12/27/2018 4:15 PM, Arthur Delibert wrote: > You may also want to check out the SAL-12, -20 or -30 antennas from > Array Solutions. My yard is pretty small, but I was able to put up a > SAL-12, and I love it. (I do mostly 49-, 60- and 90-meter SWBC DX.) > I can switch the antenna to any one of 8 different directions, and I'm > often surprised to find that the DX is coming from a direction different from > what I would expect. > Often there's a very pronounced peak in the signal when the antenna is > pointed in the right direction, and I really would not have had any > copy if I couldn't point in that direction. > > The SAL-12 isn't especially good on 160, but is good from 3 MHz and > higher. The SAL-20 and -30 are reportedly very good on 160. If I > recall right, the > SAL-20 is directional up to 20 meters; the SAL-30 is good up to 40 > meters. Check the Array Solutions website to confirm. > > These aren't as cheap as putting up your own pennant, but above 3 MHz, > the > SAL-12 aimed NE almost always outperforms my pennant pointed in the > same direction. > > Regards, > Art Delibert, KB3FJO > > -- > -- _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Unofficial archive of the works from the early pioneers of Amateur Radio's digital communications era
What is CCW? Amateur Radio Coherent CW was invented by Ray Petit, W7GHM. He is also the inventor of Clover now manufactured by HAL Communications. The first amateur QSO was by Andy McCaskey, WA7ZVC using a Ten-Tec PM-1. CCW was promoted by Chas. Woodson (Woody), W6NEY a professor at Stanford University. Woody published a newsletter in the early 1970's. Ade Weiss, W0RSP wrote some articles in CQ and Woody, W6NEY publish a series of articles in QST in 1979 - 1981 period. In February 1994 VE2IQ published his circuit for CCW using a PC and DSP techniques. Peter Lamb, G3IRM wrote a newsletter on CCW techniques in the early 1990's. CCW moved on to BPSK techniques and is presently being used on 80 meters. A lot of this work, software, etc. is available on the web. The ARRL had information in the 1980's handbooks and still has some material in the current issues. Amateur CCW was developed before we had nice microprocessors, DSP and other current technology. It's been around for 25 years, is only as complex as an SSB transmitter, and certainly within the building ability of all most all amateurs. One does not need power ... it is a QRPp mode. CCW is slow ... 12 wpm CW. You need a good freq standard, but today we can use GPS timing (see TAPR web site). It works in noise and under poor conditions and has been proven to work on the ham bands. See all that here. https://midnightdesignsolutions.com/ccw/ 73 JC N4IS -Original Message- From: Topband On Behalf Of JC Sent: Monday, December 24, 2018 6:46 PM To: 'K4SAV' ; topband@contesting.com Subject: Re: Topband: FT8 - How it really works Jerry The new mode FT8 is not all that new, actually, there are several aspects to consider, like detect the signal, decode the signal detected, make a decision to accept the decoded signal. The improvement on signal to noise ratio concept is very old, just the internet made it possible with time synchronization. The decode uses new algorithms and some very intelligent way to guest the decoded signal. Check this out. 1975 Sept QST; Coherent cw test! Experiments show 20 db Signal Boost over QRM, http://www.arrl.org/files/file/Technology/tis/info/pdf/7509026.pdf The improvement on signal to noise ratio is just because a narrow bandwidth. The gates opens at the right millisecond window. On FSK the secret salvage is time synchronization. You can record the audio and play it back, the decode will happen only if you synchronize the time of the recording with the time in ms of the PC clock. I did that, and it worked, I have a SDR QS1R and using HDSDR software to record the I/Q file, RF file. I used to record rare DX expedition signal and the bandwidth is 50 KHz, I can see the FT8 guys on 1840, My question was , can I decode them from the digital file recorded several month ago? I started plaining the file at the top of the second count, and voalah!!!, The WSJT-X decoded several station, weak as -21 db. The weak signals are there, buried in the noise on my old digital recorded file. Then I decided to test my HWF, the practical result measuring cw signal is that the signal to noise increase around 20 db, 10 db due the directivity RDF 11.5 and another 10 db from the polarization filter. The Horizontal WF attenuation on vertical signals is over -90 db. The manmade noise vertical polarized is reduced below the MDS of the receiver and cannot be amplified by the receiver. The IC-7800 has two identical receivers. I connected my HWF on receiver MAIN and the TX antenna on the receiver SUB, I installed two instances of the WSJTX program, one for each receiver. After 15 minutes the number of decodes on the HWF was 20 or times more than the vertical full size vertical, my TX antenna 120 Ft high. Signals decoded around -21 db on the vertical was decoded on the HWF 0 to +1 db. Signals less the -5db decoded on the HWF was not decoded using the vertical, The HWF was decoding hundreds of signals that would be -40 db on the decode using the vertical. I think the s/n reported by the program as ball part is actually very good and close to the real s/n improvement of 2 Hz BW, depending on the mode. The only real way to increase signal to noise ratio is increasing the directivity of the RX antenna, more real RDF means real signal to noise ratio improvement. I used real because it is very easy to destroy the directivity with integration, leaking, intermodulation, low noise figure etc. One bad concept, bidirectional unterminated beverage with two lobes one in the back and one front, it just does not work because the RDF is 6 db down a terminated beverage. Same for BOG's the RDF is bad, a K9AY works better because has more RDF. A simple Flag can deliver 9 db RDF is tis easy to hide too. Two Flags in phase 11.5 db and four Flags 14 db RDF, and a very clean pattern besides real broadband from 1 MHz to 10 MHz As you can see on the ARRL 1975 article, there is nothing new about improvemen
Re: Topband: capacity needed for Detuning tower
Terry My tower is 116 high , plus 10 ft of mast with a top hat, and the HWF. I never had any problem on 80m because the antenna is too long and near 1/2 wave vertical for 80m, my Vertical WF is 60 ft from the tower and I never noticed any degradation on the irradiation diagram measured with polar plot. My friend Peter N8PR used to have the K8UR four square for 80.. It worked very well on 80m, however the dipole side connected to the coaxial braid, connected to the phase box than connected to another coaxial and the other dipole connected to the braid, all this connected forms a 1/2 wave on 160m. Peter antenna on 160m is very similar to my but his signal was always 10 db lower than my on 160m, the 1/2 wave formed by the 80m dipoles was changing the irradiation patter on 160m, simulating on EZNEC we found that the signal was going up and not low angle as it should be on 160m. Peter disconnected the 80 dipoles from the phasing box and immediately his 160m signal become very similar to my signal on all RBNs that we were able to check. Saying that, John K9UWA detuned his tower and his 4 square improved a lot. The way to find the capacitor value is using a small variable capacitor in series with a MFJ 259, adjust the capacitor for zero ohms reactance on the MFJ meter. Luis IV3PRK has on his site a detailed description how to detune the tower using antenna analyzers, here http://www.iv3prk.it/detuning-tx-ant..htm http://www.iv3prk.it/user/image/site2-rxant.prk_detuning-tower.pdf 73's JC N4IS -Original Message- From: Topband On Behalf Of John Kaufmann Sent: Saturday, December 22, 2018 7:12 AM To: 'terry burge' ; topband@contesting.com Subject: Re: Topband: capacity needed for Deturning tower On 160 I've used a vertical wire of 20 feet with a 1000 pF variable capacitor to detune a tower at its base. You can scale that to 80. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of terry burge Sent: Friday, December 21, 2018 9:22 PM To: topband@contesting.com; terry burge Subject: Topband: capacity needed for Deturning tower Hi again, This may not be possible to answer with anything like 10% accuracy but can someone give me an idea just how much capacitance I need for putting up a 50-55' vertical wire up the lower half of my tower to detune it on 75 meters around the DX windown (3790-3800 Khz). The tower is Rohn 55 with 117' above ground. A 3 element 20-6 mtr Steppir at 118', a GP6 at the very top with peak at 134' and a 40 meter dipole (63' or so) at 104'. I have my K8UR style 4-Square around the tower with the lower half of the slopers pulled in towards the tower. Since I've not been able to get a beverage or bog to work due to a lot of noise I'm going to run a detuning line up to below my Comtek unit at 64' and try detuning the tower. But I just don't know what to expect to need for capacitance to detune the tower. Terry KI7M _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Waller Flag
Stan Yes, for each one db improvement on RDF you can expect 2 or more dB on signal to noise ratio. One simple solution for you is to phase two or 4 delta flags, it will provide over 14 db RDF and only 50m long. 73’s JC N4IS From: Stan Stockton Sent: Saturday, December 15, 2018 3:28 PM To: n...@n4is.com; topband@contesting.com Subject: Re: Topband: Waller Flag Thanks, JC. Based on what you said and what I know about the location, I think I probably have enough noise that I shouldn't have to worry about how much gain the preamp might have relative to the negative gain of the smaller antenna. My plan would be to install it horizontally at about 64 feet above a tribander. If I can make it all work, it would be the greatest improvement to my little station that could possibly be made. I have worked VU2 and some other good stuff with what I have tried in the past, but there is no question that I transmit a lot better than I receive on 160m. I see in the model I have that going to 750 feet high increases gain by about 17 dB and RDF by about 3 as compared to where I can put it. I would be very pleased to make a noticeable improvement over the little triangle antenna and have something that is on my tower that I could rotate. 73...Stan. On Sat, Dec 15, 2018 at 2:04 PM mailto:n...@n4is.com> > wrote: Hi Stan There are two very important numbers to consider, first is horizontal or vertical, the horizontal signal is zero at ground level and maximum at 1.5 wave length height , vertical signal is maximum at ground level and minimum at 1.5 wave high. The second is the gain, the local noise limits the gain, if you are on a very quiet location bigger loops can dig weaker signal out of the noise. Vertical WF can be small, 6 or 8m are common, you only need a low noise preamplifier 2db or better, gain is not important , 20 db external gain is enough on 160m. Horizontal is more challenging you need a < 1db NF. I am working on a project using two SDR receivers to phase the loops by software, it should be possible to reduce the size of the boom. But not the height necessary because the limitation is the horizontal receiver signal intensity. For horizontal average performance on 160m it is necessary 20 m above the ground, 10m high for 80m. Good performance on 160m it is necessary 30 to 40 m above ground, and it shows no limitation on performance. Higher is always better. Check vertical W8VVW (8m) WF or WX4D ( 10m) original WF. Regards JC N4IS -Original Message- From: Topband mailto:topband-boun...@contesting.com> > On Behalf Of Stan Stockton Sent: Saturday, December 15, 2018 2:15 PM To: topband@contesting.com <mailto:topband@contesting.com> Subject: Topband: Waller Flag I am curious to know if anyone on here has scaled a Waller Flag to a smaller antenna and had any success with whatever might be available for preamps to bring the gain up enough to start to hear band noise. At my location on Cayman Brac I could probably get by with a 20 foot boom but not much larger. According to my model, one with a 50 foot boom is about -48 dB, one with a 30 foot boom is about -65 dB and one with a 20 foot boom, like I would lilke to put up, is about -79 dB. I guess a lot to do with how successful the antenna might work for me will have to do with how much preamplifier gain I will need at my particular location to start to hear noise. I wanna use it on 160, 80 and 40 and the gain of the 20 foot boom one is enough for 80 and 40 using a 30 or 40 dB preamp. Any help would be appreciated. 73 and Merry Christmas...Stan, K5GO/ZF9CW _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Waller Flag
Hi Stan There are two very important numbers to consider, first is horizontal or vertical, the horizontal signal is zero at ground level and maximum at 1.5 wave length height , vertical signal is maximum at ground level and minimum at 1.5 wave high. The second is the gain, the local noise limits the gain, if you are on a very quiet location bigger loops can dig weaker signal out of the noise. Vertical WF can be small, 6 or 8m are common, you only need a low noise preamplifier 2db or better, gain is not important , 20 db external gain is enough on 160m. Horizontal is more challenging you need a < 1db NF. I am working on a project using two SDR receivers to phase the loops by software, it should be possible to reduce the size of the boom. But not the height necessary because the limitation is the horizontal receiver signal intensity. For horizontal average performance on 160m it is necessary 20 m above the ground, 10m high for 80m. Good performance on 160m it is necessary 30 to 40 m above ground, and it shows no limitation on performance. Higher is always better. Check vertical W8VVW (8m) WF or WX4D ( 10m) original WF. Regards JC N4IS -Original Message- From: Topband On Behalf Of Stan Stockton Sent: Saturday, December 15, 2018 2:15 PM To: topband@contesting.com Subject: Topband: Waller Flag I am curious to know if anyone on here has scaled a Waller Flag to a smaller antenna and had any success with whatever might be available for preamps to bring the gain up enough to start to hear band noise. At my location on Cayman Brac I could probably get by with a 20 foot boom but not much larger. According to my model, one with a 50 foot boom is about -48 dB, one with a 30 foot boom is about -65 dB and one with a 20 foot boom, like I would lilke to put up, is about -79 dB. I guess a lot to do with how successful the antenna might work for me will have to do with how much preamplifier gain I will need at my particular location to start to hear noise. I wanna use it on 160, 80 and 40 and the gain of the 20 foot boom one is enough for 80 and 40 using a 30 or 40 dB preamp. Any help would be appreciated. 73 and Merry Christmas...Stan, K5GO/ZF9CW _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Rather use N-type (was Re: The answer to PL-259 soldering/reliability problems)
The issue with PL-259 is the leaking of common mode current into the internal RF current. On higher bands the leaking is very bad but difficult to see or understand. I went to over 50 WF installation on contest station, DX station, city lot QTH and very quiet rural areas. I noticed several problems with pl259 contact between the braid and the connector and between the male and female connector as well. Using a 40 db gain preamplifier is like using a huge magnifier lent, I notices the noise floor going from s0 to s7 just moving the cable up and down, the braid was break inside the PL259. Hard to detect and all works fine if you don't check with the right tool. The N connector has an internal ring to connect the RF coaxial current , the external tread ring is just for mechanical and water proof protection with the "O" ring inside. No leaking. "N" connector as well PL259 requires a mechanical reinforcement of the cable, using 2 inches of heat shrink tube dual wall with glue is almost mandatory to avoid problems in the future. Price is no longer an issue for N due large use on WIFI, and new wireless products, the same thing with SMA connectors for RX signal path, the price is good for the quality you get. I am using N connectors as much possible in the last 30 years. My suggestion for protection is auto fusion # 2155 from 3M TemFlex Rubber Splicing Tape. It create a solid rubber cover tight to the connectors, really seal from water. Easy to remove without glue damage on the connector. I've seen 20 years old connector looking like new when I removed the tape protection. It is available on any Home Depot. PL259 makes your station noisy and you just don't know it. 73's JC N4IS Original Message- From: Topband On Behalf Of N2TK, Tony Sent: Thursday, December 6, 2018 10:31 AM To: 'GEORGE WALLNER' ; topband@contesting.com Subject: Re: Topband: Rather use N-type (was Re: The answer to PL-259 soldering/reliability problems) I have been using PL-259 connectors forever. I have switched to crimp connectors when I need to make up a new cable. No sense replacing the soldered connectors if they are working fine. ThePL-259 is a low loss, easy to assemble connector for up to at least 6M (nothing higher in frequency here) that makes good contact and are easy to seal with rescue tape followed by Scotch 33+. Some of my PL-259's have been in use outside for 40 years and still look good and work well. I hope manufacturer's don't change. 73, N2TK, Tony -Original Message- From: Topband On Behalf Of GEORGE WALLNER Sent: Thursday, December 06, 2018 9:13 AM To: topband@contesting.com Subject: Re: Topband: Rather use N-type (was Re: The answer to PL-259 soldering/reliability problems) Greg, I completely agree. For all my outdoors applications I use N connectors. Unfortunately, amateur radio gear (even seriously expensive gear) is still built with SO-239 connectors which perpetuate the use PL-259 male connectors. As a result, my station and my DXpedition gear contain both, necessitating the use of adaptors. How do we convince manufacturers to change? 73, George AA7JV/C6AGU On Thu, 06 Dec 2018 17:00:53 +1300 Greg-zl3ix wrote: > > > I continue to be mystified by the fact that the amateur radio > community insists on using PL259 connectors. N-type are much more > reliable (used by professional communicators), low cost, can be > crimped easily and quickly and have a well-defined impedance right up > into GHz frequencies. > > Back in 2005 I started having contact problems with the connector on > my SteppIR 3-element. There was a thin layer of oxide that built up > around the centre pin of the PL259. I had had similar problems with > other connectors around my shack. I decided to change my entire > station, including the SteppIR, to N-type, and have never looked back. > > > 73, Greg, ZL3IX > > On 06.12.2018 13:29, Steve Ireland wrote: > G'day >> >> About five years I discovered this fool-proof and brilliant > way to solder PL-259s invented by Bill Maxon N4AR who taught this to > Tim K3LR. Tim uses this method throughout his contest station and did > a great job of documenting it - see > http://www.k3lr.com/engineering/pl259/ > [1] and it has totally changed my angry and worried attitude towards > soldering PL-259s. >> >> The key component is Amphenol 83-1SP connectors. > The connector body is silver and the shell is nickel and you can buy > them from Mouser or DX Engineering. >> >> Vy 73 >> >> Steve, VK6VZ >> > --- >> This email has been checked for viruses by Avast antivirus > software. >> https://www.avast.com/antivirus [2] >> _ > Searchable Archives: http://www.contesting.com/_topband [3] - Topband > Reflector > > >
Re: Topband: Vertical antennas aren't always best for DX
John I think I understand where we disagree. Most low dipoles on 160m are 30 to 60 ft high, 1/4 wave high is not low for most stations. Very few can afford a dipole at 120 ft high. You right 50% is a ball parking number but it brings the attention to the importance of 3D and separation between horizontal and vertical polarization. In special on 160m, where I am a firm believer on two different propagation path, one vert, and another horizontal. By the way, what you mentioned about QSB is true, I observed this phenomenon since the first year with the HWF in 2009. QSB is just a shift in polarization between horizontal and vertical. 73's JC N4IS -Original Message- From: John Kaufmann Sent: Tuesday, November 27, 2018 9:36 AM To: n...@n4is.com; topband@contesting.com Subject: RE: Topband: Vertical antennas aren't always best for DX JC, You said: " Every dipole or inverted V irradiate 50% of the power horizontal polarized broadside with the wire and 50% of the power vertical polarized along the wire." You cited EZNEC as evidence. I am merely pointing out that as a general rule, this is not true. The issue *is* math because that is precisely how you determine the fraction of power that goes into horizontal polarization and into vertical polarization. As I pointed out, the relevant math is a 3-dimensional integration of the radiation pattern in spherical coordinates. Take a dipole that is 1/4 wavelength high, which we can all agree is "low" in wavelength terms. At a takeoff angle of 90 degrees (straight up), EZNEC shows that the horizontal and vertical components of radiation are about the same. It is easy to think there is a 50/50 split in horizontal/vertical power because of this. However, this neglects the radiation at lower angles where the large majority of the radiated power is produced. At a 45 degree takeoff angle, the broadside horizontal power dominates the vertical power by about 4 dB and the ratio increases at lower angles. If the dipole is higher than 1/4 wavelength, the ratio becomes even greater. The math does not lie. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com Sent: Tuesday, November 27, 2018 8:50 AM To: jkaufm...@alum.mit.edu; topband@contesting.com Subject: Re: Topband: Vertical antennas aren't always best for DX John The issue here is not math. It is the interaction of fields and matter. A good text book is Electromagnetic waves and radiating system by Edward C Jordan and Keith G. Balmain. Chapter 9. You can not ignore the close proximity with ground on 160m antennas for both transmit signal and receiving signal. Too close it became more a transmission line, getting high the irradiation increase and the maximum horizontal power radiated or receiving signal intensity are near 1 ½ wave high. The take off angle depends on the ground itself. 73s JC N4IS From: John Kaufmann Sent: Tuesday, November 27, 2018 8:16 AM To: n...@n4is.com; topband@contesting.com Subject: RE: Topband: Vertical antennas aren't always best for DX In considering the *total power* radiated by any antenna, you need to look at the 3-dimensional antenna pattern, not a 2-dimensional slice. The total radiated power is the 3-dimensional integration of the 3-dimensional radiation pattern. It is convenient to do this in spherical coordinates because that is how we visualize 3-dimensional patterns. In spherical coordinates the integration applies the *smallest* weighting at elevation angles around zenith. Even if the dipole is low, the calculation shows that the fraction of power that goes straight up is small compared to the total radiated power. This is easily understood in 3-dimensional spherical coordinates: https://www.khanacademy.org/math/multivariable-calculus/integrating-multivar iable-functions/triple-integrals-a/a/triple-integrals-in-spherical-coordinat es. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com <mailto:n...@n4is.com> Sent: Tuesday, November 27, 2018 6:58 AM To: jkaufm...@alum.mit.edu <mailto:jkaufm...@alum.mit.edu> ; topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX Sorry , but all antenna's on 160m are close to the ground and it is the case, you can check by yourself using EZENEC if you don't know how to calculate the fields. There is no misleading here. 73 JC N4IS -Original Message- From: Topband mailto:topband-boun...@contesting.com> > On Behalf Of John Kaufmann Sent: Monday, November 26, 2018 8:53 PM To: topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX The statement that the half of a horizontal dipole's radiation is verticall
Re: Topband: Vertical antennas aren't always best for DX
Hi John On EZNEC for sure 3D. do not use total field, under description select horizontal and vertical field only and see the red line , vertical field and green line horizontal field, use real ground. Look it again. 73's JC -Original Message- From: John Kaufmann Sent: Tuesday, November 27, 2018 9:36 AM To: n...@n4is.com; topband@contesting.com Subject: RE: Topband: Vertical antennas aren't always best for DX JC, You said: " Every dipole or inverted V irradiate 50% of the power horizontal polarized broadside with the wire and 50% of the power vertical polarized along the wire." You cited EZNEC as evidence. I am merely pointing out that as a general rule, this is not true. The issue *is* math because that is precisely how you determine the fraction of power that goes into horizontal polarization and into vertical polarization. As I pointed out, the relevant math is a 3-dimensional integration of the radiation pattern in spherical coordinates. Take a dipole that is 1/4 wavelength high, which we can all agree is "low" in wavelength terms. At a takeoff angle of 90 degrees (straight up), EZNEC shows that the horizontal and vertical components of radiation are about the same. It is easy to think there is a 50/50 split in horizontal/vertical power because of this. However, this neglects the radiation at lower angles where the large majority of the radiated power is produced. At a 45 degree takeoff angle, the broadside horizontal power dominates the vertical power by about 4 dB and the ratio increases at lower angles. If the dipole is higher than 1/4 wavelength, the ratio becomes even greater. The math does not lie. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com Sent: Tuesday, November 27, 2018 8:50 AM To: jkaufm...@alum.mit.edu; topband@contesting.com Subject: Re: Topband: Vertical antennas aren't always best for DX John The issue here is not math. It is the interaction of fields and matter. A good text book is Electromagnetic waves and radiating system by Edward C Jordan and Keith G. Balmain. Chapter 9. You can not ignore the close proximity with ground on 160m antennas for both transmit signal and receiving signal. Too close it became more a transmission line, getting high the irradiation increase and the maximum horizontal power radiated or receiving signal intensity are near 1 ½ wave high. The take off angle depends on the ground itself. 73s JC N4IS From: John Kaufmann Sent: Tuesday, November 27, 2018 8:16 AM To: n...@n4is.com; topband@contesting.com Subject: RE: Topband: Vertical antennas aren't always best for DX In considering the *total power* radiated by any antenna, you need to look at the 3-dimensional antenna pattern, not a 2-dimensional slice. The total radiated power is the 3-dimensional integration of the 3-dimensional radiation pattern. It is convenient to do this in spherical coordinates because that is how we visualize 3-dimensional patterns. In spherical coordinates the integration applies the *smallest* weighting at elevation angles around zenith. Even if the dipole is low, the calculation shows that the fraction of power that goes straight up is small compared to the total radiated power. This is easily understood in 3-dimensional spherical coordinates: https://www.khanacademy.org/math/multivariable-calculus/integrating-multivar iable-functions/triple-integrals-a/a/triple-integrals-in-spherical-coordinat es. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com <mailto:n...@n4is.com> Sent: Tuesday, November 27, 2018 6:58 AM To: jkaufm...@alum.mit.edu <mailto:jkaufm...@alum.mit.edu> ; topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX Sorry , but all antenna's on 160m are close to the ground and it is the case, you can check by yourself using EZENEC if you don't know how to calculate the fields. There is no misleading here. 73 JC N4IS -Original Message- From: Topband mailto:topband-boun...@contesting.com> > On Behalf Of John Kaufmann Sent: Monday, November 26, 2018 8:53 PM To: topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX The statement that the half of a horizontal dipole's radiation is vertically polarized is misleading and needs qualification. There is a vertically polarized component off the ends of the dipole but it is only of consequence at takeoff angles approaching 90 degrees, in other words straight overhead. I would argue that these takeoff angles are of little interest for long distance propagation. At takeoff angles lower than 60 degrees or so, the total radiation pattern of a dipole at any re
Re: Topband: Vertical antennas aren't always best for DX
John The issue here is not math. It is the interaction of fields and matter. A good text book is Electromagnetic waves and radiating system by Edward C Jordan and Keith G. Balmain. Chapter 9. You can not ignore the close proximity with ground on 160m antennas for both transmit signal and receiving signal. Too close it became more a transmission line, getting high the irradiation increase and the maximum horizontal power radiated or receiving signal intensity are near 1 ½ wave high. The take off angle depends on the ground itself. 73s JC N4IS From: John Kaufmann Sent: Tuesday, November 27, 2018 8:16 AM To: n...@n4is.com; topband@contesting.com Subject: RE: Topband: Vertical antennas aren't always best for DX In considering the *total power* radiated by any antenna, you need to look at the 3-dimensional antenna pattern, not a 2-dimensional slice. The total radiated power is the 3-dimensional integration of the 3-dimensional radiation pattern. It is convenient to do this in spherical coordinates because that is how we visualize 3-dimensional patterns. In spherical coordinates the integration applies the *smallest* weighting at elevation angles around zenith. Even if the dipole is low, the calculation shows that the fraction of power that goes straight up is small compared to the total radiated power. This is easily understood in 3-dimensional spherical coordinates: https://www.khanacademy.org/math/multivariable-calculus/integrating-multivar iable-functions/triple-integrals-a/a/triple-integrals-in-spherical-coordinat es. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com <mailto:n...@n4is.com> Sent: Tuesday, November 27, 2018 6:58 AM To: jkaufm...@alum.mit.edu <mailto:jkaufm...@alum.mit.edu> ; topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX Sorry , but all antenna's on 160m are close to the ground and it is the case, you can check by yourself using EZENEC if you don't know how to calculate the fields. There is no misleading here. 73 JC N4IS -Original Message- From: Topband mailto:topband-boun...@contesting.com> > On Behalf Of John Kaufmann Sent: Monday, November 26, 2018 8:53 PM To: topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX The statement that the half of a horizontal dipole's radiation is vertically polarized is misleading and needs qualification. There is a vertically polarized component off the ends of the dipole but it is only of consequence at takeoff angles approaching 90 degrees, in other words straight overhead. I would argue that these takeoff angles are of little interest for long distance propagation. At takeoff angles lower than 60 degrees or so, the total radiation pattern of a dipole at any reasonable height becomes dominated by the horizontally polarized component that is broadside to the dipole. The lower the angle or the higher the dipole, the more insignificant the vertical component becomes. This is all verifiable in EZNEC. If this were not true, you would not see the well-defined radiation patterns that are produced by HF Yagi's at higher frequencies were the radiation is horizontally polarized for virtually all signals of interest. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com <mailto:n...@n4is.com> Sent: Monday, November 26, 2018 11:06 AM To: 'Roger Kennedy'; topband@contesting.com <mailto:topband@contesting.com> Subject: Re: Topband: Vertical antennas aren't always best for DX Roger Every dipole or inverted V irradiate 50% of the power horizontal polarized broadside with the wire and 50% of the power vertical polarized along the wire. After the first refraction it does not matter. This is an electro-magnetic wave law. You can check that on EZENEC, it is not a anecdote. The advantage over vertical 1/4 wave antenna is efficiency. The vertical efficiency depends on the ground plane resistance, it is common to see invert L with only 50 % irradiated power, the other 50% is dissipated on the ground. "In Theory, we know everything, but nothing works" "In Practice, everything works, but we don't know why" We never will fully understand the 160m band. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Vertical antennas aren't always best for DX
Sorry , but all antenna's on 160m are close to the ground and it is the case, you can check by yourself using EZENEC if you don't know how to calculate the fields. There is no misleading here. 73 JC N4IS -Original Message- From: Topband On Behalf Of John Kaufmann Sent: Monday, November 26, 2018 8:53 PM To: topband@contesting.com Subject: Re: Topband: Vertical antennas aren't always best for DX The statement that the half of a horizontal dipole's radiation is vertically polarized is misleading and needs qualification. There is a vertically polarized component off the ends of the dipole but it is only of consequence at takeoff angles approaching 90 degrees, in other words straight overhead. I would argue that these takeoff angles are of little interest for long distance propagation. At takeoff angles lower than 60 degrees or so, the total radiation pattern of a dipole at any reasonable height becomes dominated by the horizontally polarized component that is broadside to the dipole. The lower the angle or the higher the dipole, the more insignificant the vertical component becomes. This is all verifiable in EZNEC. If this were not true, you would not see the well-defined radiation patterns that are produced by HF Yagi's at higher frequencies were the radiation is horizontally polarized for virtually all signals of interest. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of n...@n4is.com Sent: Monday, November 26, 2018 11:06 AM To: 'Roger Kennedy'; topband@contesting.com Subject: Re: Topband: Vertical antennas aren't always best for DX Roger Every dipole or inverted V irradiate 50% of the power horizontal polarized broadside with the wire and 50% of the power vertical polarized along the wire. After the first refraction it does not matter. This is an electro-magnetic wave law. You can check that on EZENEC, it is not a anecdote. The advantage over vertical 1/4 wave antenna is efficiency. The vertical efficiency depends on the ground plane resistance, it is common to see invert L with only 50 % irradiated power, the other 50% is dissipated on the ground. "In Theory, we know everything, but nothing works" "In Practice, everything works, but we don't know why" We never will fully understand the 160m band. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Vertical antennas aren't always best for DX
Roger Every dipole or inverted V irradiate 50% of the power horizontal polarized broadside with the wire and 50% of the power vertical polarized along the wire. After the first refraction it does not matter. This is an electro-magnetic wave law. You can check that on EZENEC, it is not a anecdote. The advantage over vertical 1/4 wave antenna is efficiency. The vertical efficiency depends on the ground plane resistance, it is common to see invert L with only 50 % irradiated power, the other 50% is dissipated on the ground. "In Theory, we know everything, but nothing works" "In Practice, everything works, but we don't know why" We never will fully understand the 160m band. 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Vertical antennas aren't always best for DX everywhere - the facts
Hi Frank I can comment on horizontal polarization. I am experiencing both polarization since 1980; with a vertical and a inverted V at 30m and 40m later; also with high DRF receiving antennas like the HWF and VWF since 2006. Here my 2 cents. There are 3 steps. 1. Make the power out of your antenna. 2. Get the wave up to be refracted down. 3. After refracted the wave get propagated. These 3 different things need attention. I will comment 3 to 1 3- * Does not matter the original polarization after the wave refract it splits in horizontal and vertical polarization. * The propagation is different for both waves, ordinary and extraordinary. * The attenuation is also different during the path. It is normal for me here in South Florida, 23 degree North, to hear VK6 on horizontal HWF 30 minutes before SR coming from 210 degree SSW, and nothing on the VWF vertical, then at Sunrise’ the signal change to direct path W and peak at SR only on the VWF, no copy on the HWF. * W8JI did not have a horizontal RX antenna with high RDF to compare with high RDF RX antennas. 2 * The direction is very important, N-S is affected by the inclination of the earth magnet field. Signals from south are stronger on horizontal, there is less attenuation near the equator for horizontal pol. * Working stations from Africa or pacific , W -E, it’s is normal to experience long and deep QSB, The polarization shift slowly between vertical and horizontal, the signal is Q5 on the Horizontal WF, after few minutes fade and become Q5 on the Vertical WF. * This is the same on 160 80 , but on not on 40m where horizontal polarization is always better. 1 * Ground interaction between matter (ground) and radio frequency wave is the same everywhere on 160m. Horizontal signal has a -1 factor and cancel signals near the ground, The inverted V or Dipole is always near to the ground on 160m (500ft), the irradiation patter is 50% vertical and 50% horizontal. * My first experience with a ¼ wave full size vertical was in Brazil back in 1990, I worked 9V1XQ with 400 w using the ¼ TX vertical. Few month later I installed a inverted V at 120 ft. high. * All A/B tests did show 10 db improvement on the inverted V over the vertical with a poor ground plane. * The issue is what kind of test you can do. Well we test SSB with local guys , 4000 miles QSO’s on CW, but it is hard to test with 8000 miles or more. * Before 2000, PY1RO had a 20 years sked with Mike VK6HD near SR and never completed one QSO. In the last 20 years there was several QSO’s PY-VK6 with signals coming from NNE near SS. Hard to tell if the vertical TX antenna was used or not on the VK6HD side. * Vertical for 160m on South America used to be very rare. Nowadays we have several great signals using ¼ wave vertical, LU8DPM , PP5JR, PY2RO and others. The difference between them and the guys using an inverted V are at least 10 db better here in Florida for the vertical antenna. * W4ZV , Bill always tell me to get and inverted V to work pacific, Bill loves his inverted V. Here in my QTH, I don’t have the space for one, but I never feel necessary because I work pacific with my Vertical and listening on the HWF all the time. Using the HWF in my city lot I just don’t hear any manmade noise from the city around me, I have common node noise under control. The signals are always weak then the HWF, but always with better signal to noise ratio then the VWF. The issue in 160m is that the HWF needs to be above 85ft. 90 is good, 120 is better and 160ft at K9CT or 200ft like W8LRL is just fantastic. The HWF works very well on 80m at 60ft high and above. RDF makes a huge difference on RX signal to noise ratio. My measurements over the last 10 year indicate for each one db increase on RDF the signal to noise ration increases two db. On 160m RX there are two very different propagation path, one horizontal and another vertical. But for TX. If it is V or H does not matter, what only matter is the irradiated power efficiency to get the wave refracted by the ionosphere. 73’s N4IS JC _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: ARRL DXCC - 160 Meters
Guys Just for clarification I mentioned a QSO on 160 between PY3 and 4W SSB low power when there is no darkness near PY3 SR, only few minutes near SS. During winter I can hear Europe on 40 m all day long in South Florida, it is very common on 40m. Not the same on 160m. 73's JC N4IS -Original Message- From: Topband On Behalf Of Wes Stewart Sent: Tuesday, November 20, 2018 2:56 PM To: topband@contesting.com Subject: Re: Topband: ARRL DXCC - 160 Meters One of our SADXA members just wrote a paper about the possibility of daytime 40-meter DX during mid-December. But on this subject I would like to know who made the ONE 160-meter SSB QSO with VP6D. Wes N7WS On 11/20/2018 11:57 AM, Clive GM3POI wrote: > JC I think you have to be careful about saying this daytime or that > qso could not have happened. "It entirely depends where the station is > located." > An example, I have a QSL with three QSOS between me and a JD1 station > all within about 15 mins of each other, on different dates and centred > on midday here on 40m. Stations in Northerly location will have a > high degree of probability for midwinter daytime DX contacts. They > will at other parts of the cycle, have a similar type of opening to > the Pacific either side of mid night on the higher HF bands. > I agree the OK stuff stinks and considering the previous qsl printing > that went on, you cannot believe any of the data for certain. > 73 Clive GM3POI > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: ARRL DXCC - 160 Meters
Hi Guys Here what I think is the problem. DXCC records and link accounts. This is a problem with CQ WAZ as well. Here some examples, Back in late 80's a PY1 send 40 cards to claim CQ WAZ 40 zones on 160m, just after HB9AMO Plaque # 1 - 13 June 1987 . K1MEM sent a letter to PY1RO to check the cards, and several cards was just impossible QSO's, like China during daytime and the Chinese station never worked on 160m. The certificate was canceled, however 10 to 20 years later the same guy apply again and get his WAZ original certificate number validate using old credits. The certificate was canceled but the filed credits not. Same thing on DXCC, after 10 years you can apply again, using link accounts, and using old credits on file. I've seen this with others PY, LZ and why not this OK. This is fixable. I understand the ARRL wants to be very discreate when someone is caught doing creative things, no moral or ethical help on publicity. So I believe it is just an internal broken process that allow linked accounts and old records to be used again without verification. The issue I see on LOTW is a lack of card check at the same level we have with paper QSL cards. Here some examples. PY3CEJ posted on his website a QSL card with a SSB QSO 11:30 am local noon time, and with only 100w. I call PY3CEJ and challenged him about this impossible QSO, few days latter the 4W guy uploaded on Club Log this fantastic QSO. If you look on the statistics there is only one single QSO on 160, 2 QSO's on 80m and 100's of QSO on 40m SSB, most with JA's. I cannot say that this QSO was uploaded to LOTW, but there is nothing to prevent it. In the last six years we've seen a large number of QSO during day time on 160m from several " groups club" , like the ongoing strong between PY, LZ and YB. QSO's on 160m on broad day sun light. Ongoing means last week with new impossible QSO's on Club Log and credits on the DXCC list latter for sure. The explanation from ARRL was that there is no way to stop "them". I don't agree with it, a simple code on LOTW DXCC validation can flag those daytime 160m QSO's for late "card check". The real thing here is the most dangerous behavior for our hobby. if you don't care I don' t mind, and I don't mind if you don't care. Please! we do care, and we do mint! Do something too!... 73's JC N4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: ARRL DXCC - 160 Meters
Hi Joel I have the same impression as Bill mentioned. 160m paper QSL requires a card checker, however LOTW confirmation does not have the same process, no QSO or QSL check at all. We've seen 160m " QSO's" on Club Log and subsequent confirmation on LOTW on plain day light. 73's JC N4IS -Original Message- From: Topband On Behalf Of w...@w5zn.org Sent: Saturday, November 17, 2018 8:12 AM To: topband Subject: Re: Topband: ARRL DXCC - 160 Meters Folks - I'm not exactly understanding the LoTW comments on this thread. If it is referring to the LoTW screen shot totals listed by OK1RD on his website then that is the combined totals in his DXCC record, not the totals confirmed solely via LoTW so a "hack" has not necessarily occurred. Regardless, there is convincing evidence some bogus QSL cards were reviewed and accepted by a DXCC card checker somewhere and then entered into his DXCC record! 73 Joel W5ZN On 2018-11-17 05:29, Bill Tippett wrote: >>> Doesn't say much for the DXCC checking process either. 73 Clive >>> GM3POI > > > Guys this was probably done by OK1RD to embarrass ARRL/DXCC, in > retaliation > > for ARRL (correctly) removing his bogus listing over 10 years ago. He > > probably found a way to hack LOTW and no human monitored the result. > I'm > > sure they will correct the listing but it does raise some serious > issues > > about the security of their system. > > > 73, Bill W4ZV > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Fwd: ARRL DXCC - 160 Meters OK1YQ (OK1RD) Legitimacy???!!!
Hi Jeff We have a similar problem with several "PY" faking QSL, QSO and even LOTW confirmation by the DX operator. We've been reporting (we.. N4IS, PY2XB , PY2RO and PY5EG), documenting on paper, talking and meeting with ARRL officials including the DXCC desk for several years, and ARRL just don’t care! This is a sad growing problem. Regards JC N4IS -Original Message- From: Topband On Behalf Of k1zm--- via Topband Sent: Saturday, November 17, 2018 5:48 AM To: lennart.michaels...@telia.com; topband@contesting.com Subject: Re: Topband: Fwd: ARRL DXCC - 160 Meters OK1YQ (OK1RD) Legitimacy???!!! FYI There is a NEW EMAIL ADDRESS for the ARRL DXCC DESK - it is dxccad...@arrl.org Pls send your comments to this email address for investigation and possible action! Thanks! 73 JEFF Vy2ZM In a message dated 11/17/2018 10:45:27 AM Coordinated Universal Time, lennart.michaels...@telia.com writes: Good idea Jeff! Thanks Peter for digging in this mudd! 73 Len/BIC -Ursprungligt meddelande- Från: Topband För k1zm--- via Topband Skickat: den 17 november 2018 11:43 Till: topband@contesting.com Ämne: Topband: Fwd: ARRL DXCC - 160 Meters OK1YQ (OK1RD) Legitimacy???!!! From: k...@aol.com To: sm2...@telia.com Cc: d...@arrl.org Sent: 11/17/2018 10:33:41 AM Coordinated Universal Time Subject: Re: Topband: ARRL DXCC - 160 Meters OK1YQ (OK1RD) Legitimacy???!!! Hmmm again Okay - now I remember this guy and his shenanigans from way back. OK1RD (now masquerading as OK1YQ - which is a callsign that does not appear on qrz.com!) Guys - I would recommend that any of us that are really interested send an email to the ARRL DXCC desk and ask that this 160m DXCC OK1YQ listing be taken down - and that this fellow be prohibited from participating in the DXCC program going forward. This is ridiculous and I agree - who is now running the DXCC desk? Sure wish NN1N and some of the older, wiser DXCC managers were still around to police this kind of activity! What utter nonsense! 73 JEFF VY2ZM In a message dated 11/17/2018 10:07:05 AM Coordinated Universal Time, sm2...@telia.com writes: If OK1YQ is OK1RD as you say Bob, then pse read: http://www.g3txf.com/dxtrip/Fake-C21XF/Fake-C21.html https://www.eham.net/ehamforum/smf/index.php?action=printpage;topic=110968.0 73 Peter SM2CEW At 00:32 2018-11-17, Bob W4DR wrote: >OK1YQ is actually OK1RD > >-Original Message- From: donov...@starpower.net >Sent: Friday, November 16, 2018 7:06 PM >To: topband >Subject: Re: Topband: ARRL DXCC - 160 Meters > > >JC, > > >I have well over a million QSOs in my computer log but not even a >single QSO with OK1YQ > > >73 >Frank >W3LPL > > >On 2018-11-16 13:32, n...@n4is.com wrote: >>I never heard him on any band but he must be very active on EME >> >>ARRL DXCC - 2 Meters -151 OK1YQ >> >>http://www.arrl.org/system/dxcc/view/DXCC-2M-20181116-USLetter.pdf >> >>73's JC >>N4IS >> >>-Original Message- From: Topband >> On Behalf Of uy0zg >>Sent: Friday, November 16, 2018 1:41 PM >>To: Topband@contesting.com >>Subject: Topband: ARRL DXCC - 160 Meters >> >> >> >>ARRL DXCC - 160 Meters -339 OK1YQ . >> >>Who is it ?? >> >>http://www.arrl.org/system/dxcc/view/DXCC-160M-20181116-A4.pdf#page=1&; >>zoom=a >>uto,-12,848 >_ >Searchable Archives: http://www.contesting.com/_topband - Topband >Reflector > >_ >Searchable Archives: http://www.contesting.com/_topband - Topband >Reflector _ Searchable Archives: >http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Vertical and horizontal polarized antennas in the same space (was Propagation improves from VK6 into Europe)
Hi Steve. You are 100 % right, the V works like a top hat for a vertical TX antenna. I it simple to detune any vertical TX antenna. Vertical TX antenna is the only way to work DX on topband! You may ask about the inverted V or low dipole, they are not 100% horizontal, actually they are 50% horizontal on the broadside and 50% vertical along the wire. Ground reflects horizontal signals -1, it means 180 degree out of phase, and the reflected signal cancels the arriving signal, The Arriving signal is maximum only near 1 1/2 wave high above ground 750ft!!!. The vertical reflected signal has +1 and add to the arriving signal producing gain, ground gain. Detuning a TX antenna is like a LC circuit, you need high impedance between the antenna and the ground. The UNIPOLE or cage antenna works very well to detune grounded towers up to 30 db, and it is easy to feed with 200 ohms, becoming a very large broadband antenna. Isolated towers or inverted V is the same, they need high isolation from ground. I sed the same configuration for over 20 years, the open line works very well 80 - 10m. Regards JC M4IS _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: ARRL DXCC - 160 Meters
I never heard him on any band but he must be very active on EME ARRL DXCC - 2 Meters -151 OK1YQ http://www.arrl.org/system/dxcc/view/DXCC-2M-20181116-USLetter.pdf 73's JC N4IS -Original Message- From: Topband On Behalf Of uy0zg Sent: Friday, November 16, 2018 1:41 PM To: Topband@contesting.com Subject: Topband: ARRL DXCC - 160 Meters ARRL DXCC - 160 Meters -339 OK1YQ . Who is it ?? http://www.arrl.org/system/dxcc/view/DXCC-160M-20181116-A4.pdf#page=1&zoom=a uto,-12,848 -- Nick, UY0ZG _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: 40m array as RX antenna
Lee I agree with you, a vertical array in a quiet place works very well, I remember our friend Dale. The 8 circle array has almost 13 db RDF and can hear better than the WF with 11.5db RDF. The issue is city lot with tons of noise from everywhere. Small back yard with all cables tower and other wires nothing vertical works there. Several contest stations have problems with beverages due to much towers. Unfortunately situation is getting wroth every year, I am not using my vertical WF anymore, the noise level with LED and Variable speed motor drives, is becoming unbearable on the city. Friday and Saturday people here charge the battery of their boats to enjoy the weekends at the sea, what a mess, noise from everywhere. The noise on my vertical antenna is s9 during the week and s9+10 during weekends. EWE, loops and flags need low NF and good shield. I am just reporting what I see helping people to install WF's. Most station have serious problem with common mode noise. I would suggest a metal box to protect any RX system, it does help. You never know what you are missing if you have nothing to compare with. I understand price point is always an issue. Regards JC N4IS -Original Message- From: Topband On Behalf Of l...@k7tjr.com Sent: Wednesday, November 14, 2018 6:28 PM To: 'topband' Subject: Re: Topband: 40m array as RX antenna JC thanks for helping Jamie, I agree with most things you have pointed out however I must take issue with you on never use plastic boxes. I have used plastic boxes on my arrays for many years now and it has been very successful. The decision to use a plastic box or not depends mostly on the signal levels expected in the circuitry. My take on this is that the Waller flags have a very low signal output which requires extreme low noise and high gain amplification. The phased vertical arrays such as I make have a much greater signal output level and have never shown any ill affects using plastic. There is no need for my customers to go on a mission to change all their arrays to metal boxes. As far as DX is concerned I wish my very good friend Dale N4NN from Florida was still around because he and I would compare what you were hearing and what he was hearing. He always reported to me he would hear everything you did with his Hi-Z 8 array. I suspect the difference as you say was he was in the country without a lot of vertically polarized noise where your recording clearly indicate considerable power line noise on your VWF compared to your HWF. Eliminating local noise is quite a process of peeling back the layers one at a time. Without any other tools your best noise finding friend is a small transistorized BC band radio. It is amazing what you hear when you place one near different powered objects in your area. Put one next to your TX antenna and you will find noises and signals that are reradiated. Put one next to your computer monitor and you are likely to faint. The biggest problem we see is RG-6 coaxial cable that has been contaminated and the shield connection is damaged. To a great degree that causes all directivity to be compromised as the array then electrically looks just like a bunch of wire laying on the ground. Interesting that you indicate some say front to back does not affect RDF but this I will assure you, if you have an array that does not show significant front to back you can be rest assured the array will not have much RDF. The writings of Jim K9YC are very valuable for knocking down local noise in any RX antenna. He has addressed this many times. Keep us posted Jamie if you need more information. Lee K7TJR Hi-Z Antennas Hi Jaime The only way to really improve signal to noise ratio is with directivity. Better directivity better signal to noise ratio. Everything else is just less deterioration or more deterioration. The only thing that makes a difference is how narrow the front lobe really is. Your 40m array plus the integration with your tower and inverted L is giving you a better directivity. Probably if you try another direction the results should be very different. Things that people believe but does not impact signal to noise ratio. 1- Front back. 2- Noise canceling devices , (only help with weak signal it its narrow the front lobe) 3- Vertical array, if you live downtown, or a city lot like mine, 150x 100 ft back yard. The manmade noise is only vertical polarized, vertical array may help you to hear more noise. If you want your vertical RX array to work, it is necessary to detune your TX antenna, and any other vertical structure above 1/8 wave high, even it is 300 ft away. 160m one wave length is 480ft long, don't full yourself. Get common mode out of your RX system input, good shield is a must, never use plastic box for any RX system part. Open frame relay is also a big problem, DC bringing noise to the amplifier, another thing. Choke and shield is your friend, but only works with
Re: Topband: 40m array as RX antenna
Hi Jaime The only way to really improve signal to noise ratio is with directivity. Better directivity better signal to noise ratio. Everything else is just less deterioration or more deterioration. The only thing that makes a difference is how narrow the front lobe really is. Your 40m array plus the integration with your tower and inverted L is giving you a better directivity. Probably if you try another direction the results should be very different. Things that people believe but does not impact signal to noise ratio. 1- Front back. 2- Noise canceling devices , (only help with weak signal it its narrow the front lobe) 3- Vertical array, if you live downtown, or a city lot like mine, 150x 100 ft back yard. The manmade noise is only vertical polarized, vertical array may help you to hear more noise. If you want your vertical RX array to work, it is necessary to detune your TX antenna, and any other vertical structure above 1/8 wave high, even it is 300 ft away. 160m one wave length is 480ft long, don't full yourself. Get common mode out of your RX system input, good shield is a must, never use plastic box for any RX system part. Open frame relay is also a big problem, DC bringing noise to the amplifier, another thing. Choke and shield is your friend, but only works with a good ground. RDF measure directivity, more RDF better reception, but every single wire , cable, tower can deteriorate RDF, you need to control that. You can hear my webinar at WWW.WWROF.ORG >> https://wwrof.org/webinar-archive/n4is-waller-flag-construction/ >> https://wwrof.org/webinar-archive/high-performance-rx-antennas-for-a-small-l ot/ Just an update from that Webinar . NX4D using a Waller Flag from a 1/5 acre lot is now at #311, confirmed on 160m. My Horizontal Waller Flag, HWF, is working very well, I can hear 4K6FO , FR , VU almost every time they are on the band.. I Heard 316 countries on 160m since 2006, but the HWF was operational only after 2010. Now I am at #299 on 160m. This is a thing people only believe when they see it happening. Almost 100 people is using WHF and VWF around the world, all of them delivering excellent performance. However it is a huge project, not plug an play at all, and it works! 73's JC N4IS -Original Message- From: Topband On Behalf Of Jamie WW3S Sent: Wednesday, November 14, 2018 2:10 PM To: topband Subject: Topband: 40m array as RX antenna I'm plagued with local noise, I live in a sub division, and have a small loet (80x180), 2 yrs ago, I tried a reversible EWE and had pretty good sucess with it, last year I tried a HI-Z 3L, and wasnt really any better than the EWE. I put the EWE up again this season, and its so-so, but have discovered that my 2 ele 40m phased verticals work great as a RC antenna.there is literraly no noise on this.signal are weak, but as this noise is S0, I can hear just about everything (OK I couldnt hear the FR last night but I heard a bunch of EU calling him)..wondering why the noise is so lowoh this array compared to my other antennas, and if thats a clue as to what may be wrong (if anything) with the others.my 160 inv l is S9 noise level, and my EWE is about S3. _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Bad Frequencies and Loop Pre-amps
The main issue with IMD is the passive IMD generated by oxidation between two metal structures or wires. The IMD's on 1810,1820, 30 40 50 etc, most of the time is irradiated on your own back yard from things like. 1- Aluminum copper oxidized contact. 2- Mast not grounded to the tower, it needs a flat cable to ground it, rotor is not a grounding point. 3- Rust bolts on towers. 4- Bad overheated BALUN on low band antennas. 5- House wires connected direct to diodes on security devices power supply, like cameras or motion detectors. I don't have any nearby IMD on 160m during the night. Sometimes a weak signal come and go during day time. About the remote preamplifier, please don't believe on most project construction pictures you see on internet using plastic box, open frame relays, coaxial open at the end soldered on connectors. The real issue here is to amplify only the signal received from the loop and not add common mode noise from the cable, DC line, and the circuit itself if not shielded with a good metal box. 2000 ft of cable is a good antenna even if grounded 10 inches or more. Choke is a "must" but does not fix everything. Balanced feed line does help a lot, you can parallel to coaxial cable, ground the shield and use the two center conductors. Like the center connector of two RG58 give you 100 ohms, two RG8 150 ohms, then you need a good BALUN and lots of shield. Best is unshielded twisted pair, no common mode ground. No pain no gain! 73's N4IS JC -Original Message- From: Topband On Behalf Of Roger Kennedy Sent: Tuesday, November 13, 2018 8:25 AM To: topband@contesting.com Subject: Topband: Bad Frequencies and Loop Pre-amps I have never received ANY harmonics or intermod products from any of our British Medium Wave (AM) broadcast stations. That's at several different QTHs, some of which were quite near the transmitters. (and never heard of anyone else having issues) They have to meet VERY high specs . . . but also, most are less than 1kW ! (one of the stations I worked for had such a good Tx site - a salt marsh - they had to turn the power down to 150 watts!) Even the very big ones are usually only 10kW. So no need to avoid the 9kHz harmonics as far as us Brits are concerned! What IS a problem is all the Russian Navigation Beacons in the Baltic that pretty much wipe out everything between 1810 and 1820 kHz, so please try and avoid that part of the band if you want to work any EU ! (they sometimes turn them all off . . . but they are on most of the time.) The pre-amp I use on my 6ft 160m receiving loop is actually the design MFJ use in their 1026 noise canceller (I have a 1025 but copied their preamp design, as it uses the same pcb) . . . I get no intermod during contests, even though many EU stations are 45dB over S9 ! Roger G3YRO _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Poor conditions in 2018 so far for working VK6 to NA long path
Hi Dave We just can wait for it. Patience., good conditions is coming to stay for several years. 73's JC N4IS -Original Message- From: Topband On Behalf Of daraym...@iowatelecom.net Sent: Monday, November 12, 2018 10:04 PM To: Steve Ireland ; Topband reflector Subject: Re: Topband: Poor conditions in 2018 so far for working VK6 to NA long path Topbanders. . . Although my geographic perspective is much different than Steve's, I concur that conditions so far this season have been very poor with the exception of an occasional bright spot. . . many nights/mornings being remarkably poor. Far inland here in the Midwest (Iowa) I go night after night listening to European stations (and mornings looking toward VK, JA, etc.) that have typically in years past been Q5 with S5/S6 signals. . . but the signals are now weak, just above the noise floor, and often uncopyable. Probably the bright spot this season has been with VK. While I have only been QRV on TB since 1987 (many of you have me beat by two decades or more), I have gone through several sunspot cycles. The old adage that low sunspot numbers bring good conditions to 160m does not necessarily seem to hold true. Obviously, there are other significant factors at work (or combination of factors). I was holding my breath, hoping that the bottom of the current cycle would bring great conditions but it simply has not happened. . .at least here. A classic example is a stalwart topbander in Germany. In years past (several years ago actually) he would have S5-S8 signals, night after night, week after week, season after season. Many nights this season he is barely copyable and often not even copyable. Upon inquiring he informed me earlier in the fall he had not made any changes in his nice station. My last good skewed path opening (w/9M2 my morning hours) was September, 2010. I have seen virtually no signs of skewed path since. While all this is a bit discouraging we, of course, plod on in anticipation of better conditions to come. . .which will happen. 73. . .Dave, W0FLS -Original Message- From: Steve Ireland Sent: Monday, November 12, 2018 7:32 PM To: Topband reflector Subject: Topband: Poor conditions in 2018 so far for working VK6 to NA long path G'day With the exception of last Sunday I've been on 160m for east coast NA sunset from 7/11/18 until 12/11/18 to try to give out some ‘long path’ contacts with USA/VE. Although there has been some spotlight propagation into Europe (today was Southern Europe/North Africa and S01WS for a new country) the LP into North America has seemed to be non-existent so far. 2017 and 2016 were definitely better, with my recollection of LP openings present on several mornings during this period. My reference point is if I can hear or work Jeff VY2ZM, then I know there is a chance of working into NA further south. Every morning I regularly check Jeff's transmitting frequency - and during the aforementioned period I haven't heard Jeff once! Since Jeff started his station on PEI, we have worked on 160m many times - and on SSB at least once - and usually I can hear him virtually daily at this time of the year. This year is definitely the worse I can recall since I first came on 160m from VK6 back in 1995. I guess the take-away message is 2018 is a very bad year but east coastal NA stations don't give up hope that a LP QSO is possible (but perhaps not this season). Vy 73 Steve, VK6VZ --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Which compromise receiving antenna
Hi Pete I don't understand why Beverage at first place, A rotatable Vertical WF can perform 11.5 db RDF on 160-80-60 and 40m rotatable on any direction and it take only 50ft maximum. If you want high performance, you can build 4 delta flags in phase QDFA (0,180,180,0 degree) , enjoy 14 db RDF, 160 to 40m and needs only 150 ft long. This antenna could be reversable. I will make a commercial version next spring. You need a football field to phase 2 long beverage to get near 13 db RDF, and only works good for 160m. The HWF is another level of antenna. I am at #299 now, but heard 315 countries on 160m since 2006. Regards JC N4IS -Original Message- From: Topband On Behalf Of N4ZR Sent: Tuesday, November 6, 2018 10:40 AM To: topband reflector Subject: Topband: Which compromise receiving antenna I've just spent a very educational hour with Google Earth looking at my Beverage options for 160M. On a 45/225 azimuth I can only get about 215 feet. Is that even worth doing with a conventional Beverage? What about a BOG? Because of my lot layout I will need to use a reversible 2-wire Beverage with the NE end right outside my shack. Don't know if the KD9SV reversing transformers will work for a BOG. My other reasonable receiving option is a K9AY loop or similar. Transmitting antenna will be an inverted L, with vertical section probably no more than 60 feet. I'd like to finish my 160M DXCC this winter if possible -- 73, Pete N4ZR Check out the Reverse Beacon Network at <http://reversebeacon.net>, now spotting RTTY activity worldwide. For spots, please use your favorite "retail" DX cluster. _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Historical note: Radial Depth
Just a remind that any tower few miles!! away needs to be detuned to avoid pattern distortion. Like cellphone towers. It is the same for 160m TX tower or arrays, every tower is an antenna on low bands. 73's JC -Original Message- From: Topband On Behalf Of F Z_Bruce Sent: Saturday, October 13, 2018 11:51 AM To: 00tlziv...@bsu.edu; Topband Subject: Re: Topband: Historical note: Radial Depth AM radio stations did and still do have to meet field strength readings at contour data points. (.Ground wave field strength way point readings.). Directional antennas had to be carefully maintained. to protect stations operating on the same frequency at some distance. Radials on the earth surface are more subject to change than buried ones.. 73 Bruce-k1fz https://www.qsl.net/k1fz/bognotes.html Don't forget that historically many if not most broadcast stations, plus the legendary work of Brown, Lewis and Epstein, had their radials in farm fields and cow pastures, where anything on or near the top of the ground would be destroyed. Terry N4TZ _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: FW: [cwops] Topband season looking good
Hi topband lovers The good days of 160m propagation is back! T88UW signal was real 569 10 minutes after my SR. Ichiro is running 100W and a sloper antenna not so high. Robert DU7ET also with good signal this morning. All lovely cw signals. DX season on 160m is open and very promising. 73's JC N4IS -Original Message- From: Topband On Behalf Of Raoul Coetzee via Topband Sent: Friday, October 5, 2018 3:45 AM To: TopBand List ; CWops Groups ; FOC Reflector Cc: m...@cwops.groups.io Subject: Re: Topband: [cwops] Topband season looking good I meant to say first NA for this year! On Friday, October 5, 2018 08:46:06 AM SAST, Raoul Coetzee via Groups.Io wrote: Managed my first NA this morning around my SR on 160m.I worked Bob, W9EWZ in Wisconsin (CW of course) Raoul ZS1C_._,_._,_Groups.io Links: You receive all messages sent to this group. View/Reply Online (#27803) | Reply To Sender | Reply To Group | Mute This Topic | New Topic Your Subscription |Contact Group Owner |Unsubscribe [raoulcoet...@yahoo.com] _._,_._,_ _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: BOGs and dipoles on the ground
Hi Jerry If you want to play with a very high performance EWE array, you can try this one. 5m high , 7 m wide, 7m spaced, 4 EWE's in line. 49m total. 1st EWE 10 degree 510 ohms 2nd EWE 190 degree 540 ohms 3nd EWE 180 degree 510 ohms 4nd EWE 0 degree 540 ohms This antenna is narrow as 57 degree and punch a 13.8 db RDF, 160 to 40 m. I prefer Delta Flags on the same configuration, you can get over 14 db RDF, not much difference, but I can install it 1m over my metal fence. I am building 2 x 4 EWE at 90 degree, on a corner, and it is possible to switch 8 directions, but not with the same RDF. I hope to work JT for my last zone on 160m. 73's JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: making a bev seem longer
<< Sometimes the YCCC is better and sometimes the BOGs are better for 80m or 160m. >> That's for me is a very low performance. The good Horizontal Flag can dig signals 22 db below the vertical TX array. A simple K9AY does what you mentioned too. I heard 316 countries on 160m last 10 years, two flags can achieve 12 db DRF and you can rotate 360 degree, sharing the space with other HF antenna on the same mast. Over 300 on 80, 40 and 30 too by the way. By the way the propagation on 160m for horizontal polarized signal is different from vertical, 2010 I heard XU7ACY 80 days out of 180 days, Oct to March, on 160m SSE SSW. On my vertical politized Waller Flag I heard him just 3 times on the same period. It is nice to have more RX antennas, but ignore the Flag is a basic mistake. One flag works like two vertical in phase, very simple like that, 1 to 10 MHz, 11 to 12 db DRF. Noise is vertical polarized too if you like in a city lot like I am. Why not the flags, or EWE..??? 73's JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: making a bev seem longer
>> A BOG is an excellent choice when stealth is the driving requirement, otherwise arrays of short verticals provide significantly superior performance compared to BOG or short Beverage occupying the same physical space. << Hi Frank Any particular reason you don't mentioned FLAG's, or EWE's? Flags are easy to feed, they are broadband and have the same RDF directivity on 160,80,60,40 and very usable on 30m. 4 Phased Flags fit on 150ft and outperform a pair of phased 1000ft long beverage. The vertical flag has a low take off angle excellent for DX, 20 degree elevation lobe, and a beverage has 40 degree. Also you can turn a Flag array in all directions and a beverage is fixed in one direction, and when you decrease the frequency the front lob become so narrow that makes useless on 40 and 30m. Vertical arrays are mono band. You need one for 160 , another for 80, and if you want 40 and 30 two more. Also they needs a lot of phasing cables and a large real state area far from constructions. What am I missing here? Regards JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: RX antennas 1 + 1 = 5
Hi topband lovers The internet has become an example of bad practices resulting on wrong conclusions. Opinion are drawing based on anecdotes results where the antenna is the problem, not the lack of basic concepts that very few hams understand them. My first beverage was built with a kind of Faraday cage to isolate the primary from the secondary. Metal box was a MUST to eliminate the common mode noise from the feed line to be amplified by the preamplifier. The project was published on Ham Radio Magazine on the 70s. Today with the internet you only see new stuff. You see it everywhere and because everybody has easy access to it, its become best practice. Any receiving antenna with the same RDF has the same performance, directivity is the only way to reduce S/N ratio. But and here is the but, if dont implement the hardware correctly you dont see the result expected. You build a flag and connect to the amplifier and expect to hear the benefits of the RDF signal to noise improvement.. Simple as 1+1 =2. Most of the people that already knows everything from the internet get 1+1 =5. Wow the antenna does not work, where the extra 3 is coming from. It is not my fault, if it is from the web it is true (not really)! Any flag, beverage or any receiving antenna, even your TX antenna when used to receive have the same issue when connected using a coaxial cable. The RX antenna has only two terminals and feeds the preamp with only 2 currents. One for each terminal. The coaxial cable has 3 currents, two inside the cable and one outside the cable. Ignoring the 3rd current is a basic mistake the will deteriorate the RDF. You can see almost every where on the internet a 3:1 BALUN using a binocular core, most of them are balanced input and balanced output. Like the one you see on the LOG web site , or W8JI site or several other places. All of them uses a plastic box and a connector F , BNC, UHF or any other where the internal side of the connector is directed connected to the two wires from the BALUN secondary. Making a BALANCED to UNBALANCED connection. Just few mm of open wire on the unbalanced side of the connector is long enough to allow the 3rd current from the outside of the coaxial cable to get inside the coaxial cable mixing it with the signal coming from the BALUN primary. If you open the shield the noise from outside the shield gets inside. The two ends of the coaxial cable have this problem as well several pin 1 problems on the RX system,, open flame relays .. etc. This point is the input point of the preamplifier! ,and the gain will amplifier any signal at this end of the preamplifier feed line. How bad it could be? It depends on the intensity of both currents, if the signal from the BALUN is 30db stronger than the signal from the external coaxial shield, the deterioration will be -30 db. If the coaxial runs for 100 ft and only grounded at the preamplifier input and the preamplifier grounded on the radio input, you have almost a full size ¼ wave vertical the intensity of the external current will be the same as your TX antenna. The amplifier will overload for sure because of Am BC energy will enter the preamplifier at the plastic box we are talking about. Band pass filter is a must on 160m. The best way to avoid the 3rd current is a twisted pair feed line. The twisted pair cancel the common mode current on each twist. You can run 200ft of twisted pair without pick up any common mode noise, the twisted pair must run 10 inches far from the ground or any metal conductor. That what made the coaxial so popular, you can run dozen of coaxial cables together through the window or that PVC pipe through the wall, but not two twisted pairs. The second way is to reduce the current from outside the cable to get inside is to use a choke to attenuate the signal pick up by the coaxial cable. The way you ground the cable and where to put the choke has different results on the attenuation. Just one example, my friend IIian was operating on Afghanistan as T6LG. He was using an inverted V inside a US military base, he worked few Europeans on the first few months on 160m, after I send him instructions to build a flag using twisted pair 100 ohms striped from a Ethernet cable, Ilian worked near 1200 stations on 160 in the last 45 days on the military base. The flag is the same any shape you can make it. How it will perform depends on the feed system. When you get 1+1=5 , dont blame the antenna, try to figure out where the extra 3 is coming from. 73s JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: N7NM's book
Hi Bill I noticed that too, long path was very different past solar cycles. I am not sure if long path happened the same way before 2010. During 2010 to 2011, I heard and worked XU7ACY 50% of the days from October to March, SSE-SSW. December 31st 2011 the log path was stronger than never. Several stations on East coast worked Peter with inverted V and L's with no RX antennas. January 1st, 2012 this path just closed back the way it used to be, very rare and short duration. My take is that the size of the E clouds and the height of the ionosphere were responsible for these openings. Es is well measured at 50 MHz and above, but at 1.8 MHz, the size of the Es cloud is very large and little or no space for spot lights. The 6 meter band opened at same time the SSE SSW long path closed. The ionosphere height was very low 2010 2011 because the unusual long solar minimum. All layers was unusual close to earth. The long path on 2009 was not intense as 2010, 2011. What I am expecting is this SSE-SSW long path similar to 2010 2011 to come back after 2020 solar minimum. The difference between this and the rare long path is that the SSE-SSW long path opens every day for weeks, on 160, 80 and 40m. Another important point is the new observations on 6m about TEP along the equator, the 160m long path could be the same way because some South America stations heard XU7 and 9M2 from NNE and we SSE, the equator is between us, it is only explanation I come up with. We still have a lot to learn on SSE-SSW path. Like VY2ZM was working long path at the same time I was working XU7, both of us receiving SSE and at the center of the gray line, including Peter but receiving SSW on XU7 land. This solar minimum could bring us new lifetime events on 160m 73's JC N4IS ---Original Message- From: Topband On Behalf Of Bill Tippett Sent: Sunday, July 15, 2018 4:25 PM To: topband Subject: Re: Topband: N7NM's book N4IS wrote: Here ..page 36. https://k9la.us/NM7M_The_Big_Gun_s_Guide_to_Low-Band_Propagation.pdf I had never seen Bob's book before but thanks to JC for posting that link. There's a statement on page 93 which needs correction. Bob wrote that he had examined several logs provided by Joerg DL3DXX (including S21XX) and "I never found a single 160 meter long-path contact, NOT ONE!" Well, maybe "not one" but actually three LP contacts with S21XX (SE direction after NA sunset) that I know of (W4DR, N4SU and myself). http://lists.contesting.com/archives//html/Topband/1997-02/msg00202.html I was also surprised Bob omitted any mention of the N7UA <-> A61AJ (K1ZM op) tests in November 2000 using 4-squares at each end of the path. That test proved to me that the SW (post NA sunset) and SE (pre A6 sunrise) directions were real and not an RX antenna problem. Note that this test was done prior to publication of Bob's book in 2002. http://lists.contesting.com/archives//html/Topband/2001-09/msg00088.html Suffice it to say, we've learned much about this propagation mode in the 15 years since Bob's book was published. 73, Bill W4ZV _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 spotlight effect
<> Here ..page 36. https://k9la.us/NM7M_The_Big_Gun_s_Guide_to_Low-Band_Propagation.pdf 73's JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: TCX over salt water ..160 x 80m KH1/KH7Z Top Band Ops Brief
Here in Florida the KH1 signal on 160m was much better than 80m. Almost everyday it started s3 after an hour it was s6 to s7 and some days peaking s9 near sunrise. At the same time on 80m, the signal was always at noise level, very hard to work. The WF has better gain on 80m because at 120ft it is half wave above ground, and the size is proportional bigger than 160m in wave length. The numbers are hard to explain, but as I said here before. When you see it you will believe on it. George explained the 80m vertical was damaged by storm and removed from salt water, and installed near the salt water. The difference in propagation from 160m to 80m is average 20 db better on 80m, looking only into average signal to noise, the vertical over salt water signal on 160m was 20 db above noise floor. How to explain 40 db difference? Well it is what it is, if you can’t explain or understand it does not mean it is not there. It is like to say "based on the physics laws that bug cannot fly", but it does fly. EZENEC cannot simulate antenna over salt water. But near saltwater EZENEC can do a good job simulation results. I hope what you saw every night on 160 and 80m, made clear the TX antenna over salt water is much better, hard to explain better then near salt water. Please take the lesson for next DX expedition's. George did it again with dedication and love for top band. 73's JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Beverage Ant Thread
ve high common mode problems. The solution is to ground all cable far from our receiver, like outside the wall inside a metal box, all grounded with short straps or better an aluminum plate( 3 inches angle also does a good job) . Let that energy flow to the ground outside, don't bring it inside your radio. If you run your cables outside the tower, between trees, coming from your window, guess what! on low bands, in special 160m any RX antenna will be deteriorated and does not improve signal to noise ratio. It is not "ok" like on high bands, 20 to 10 does not have the ground wave energy the low band has. 9- Plastic box, open frame relay or switches, all of them, leaks signal inside the preamplifier input. If you open the shield the noise will come inside and deteriorate your signal to noise ratio. Shield is a "must have", my 40 db gain preamplifier requires a steel metal shield inside an aluminum shield and feedthrough capacitors .47 nF or larger, and I recommend all that inside another metal box. A 20 db gain preamplifier is not that far as shield requirements. Just because you see a lot of wrong and poor construction using plastic boxes and open frame relays does not make them right. I can keep going pealing the onion of noise layers, you only see the impact or deterioration of a noise source if it is the one on the surface of the onion, after you peal that off you will find another one on the new surface. Finding the main source of common mode noise is not easy. I used to overkill it using chokes. Chokes are you best friend against noise, but does not work if you have a poor ground system. Common mode noise and/or Pin "one" problem requires a good understanding to fix it, please check my friend Jim Brown K9YC http://k9yc.comRFI and Pin 1 Problems here http://audiosystemsgroup.com/RFI-Ham.pdf Conclusion; EZENEC give us a good understanding of your RX antenna performance, RFD can be easily calculated. Receiving antennas with same RDF should have same performance on weak signals, but .. here is the BUT .. EZENEC is a modeling program and it is based on the assumptions you input on it. Trash in >> trash out If you remove the trash, the output is perfect, however if you don't tell EZENEC all the antennas you have near your RX antenna, the TX tower, the cable outside grounded like a vertical or L shape feeding your 2m antenna, the capacitive leak from other sources, your actual irradiation diagram will be very different from the one you see on your PC screen. If you could turn your beverage like I can turn my WF you would be able to see the same deterioration on directivity as the ones I show on my webinar slides. I hope this can define deterioration and help you to avoid it. Good DX season, this will be just fantastic, be prepared top enjoy it using a good RX antenna. 73' JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Beverage Antenna Tuning
Guys Some concepts really belong to the last century, a beverage antenna is very inefficient for moderns days. Ground wave noise is very high everywhere and it is vertical polarized, any vertical polarized RX antenna will hear man made noise very well. The only really way to increase signal to noise ratio is directivity, front back actually just work on the opposite way , when you optimize front back the directivity is impacted and you increase the noise coming from the front lobe, where the DX signal is coming from. A pair of flags, or EWE's, K9AY or DHDL's, all of them are loaded loops can reach very high RDF in only 50m. You need 150 m to do what a flag can do in 5m. If you are not convinced just look again what NX4D and myself did in the last 10 years. Doug worked 311 on 160m and I am at 298, but I heard 312 countries on 160m form a city lot, my back yard is 30m x 50m, and most of them worked listening with a pair of horizontal phased loops that I call HWF. Today there are over 50 station around the world enjoying the same kind of results with HWF. My webinars on WWROF have all you need to know for a jump start. https://wwrof.org/webinar-archive/n4is-waller-flag-construction/ https://wwrof.org/webinar-archive/high-performance-rx-antennas-for-a-small-lot/ Noise is up! Common mode noise and integration between RX ant TX antennas on the same polarization is a must know concept to fight noise, and work DX on any band. 160 80 and 40 is a way to go nowadays with this deep solar activity season. You don’t need to move into the woods, efficient low band station on a city lot is a real possibility. Land is not growing and it is very expensive, noise is growing exponential. Know and believe are different things. My friend PP5JR just detuned his inverted L and his ground noise dropped 4 s units on his HWF. Now he believes what he knows for years. John K9UWA detuned all his towers on 160m and now he can say the same. Do it and believe it yourself. Regards JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Baker Island DXpedition condx
There is a fine line between "know" and "believe". Like detuning your tower, directivity increase signal to noise ratio. You need RX antenna on 160m in a quiet place. Antenna over salt water is one of those things people know but don't believe. I am 100% sure and I believe that the signal from KH1 on 160m will be solid copy several hours every day in the US East coast. I remember George signal from the same region with a simple antenna over salt water and the signal on 160m was 10 t0 20 db better then others expedition on the same region. The DHDL is not necessary, it is indispensable! same way the vertical over salt water. Propagation has being very good on 160m . Just this morning I worked Dave ZL2OK on SSB with 57 report plus QRN on 1845, lots of QRN. LU5OM and LU6YF signal was booming in here, Manuel and Juan signal was s9 on the s-meter. I has heard on VK3 and VK6 as well. Yes, QRN is a problem on the summer time, it is not so bad in the mornings but nobody say 160m is an easy band. This is the case on 160m that we never know! but I am a believer, dedication is the most important aspect on low bands, turn on your radio and call CQ! 73's N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Adding chicken wire or mesh on top of radial field
<> Hi Grant I don't know how many antennas do you install, I mean yourself. We all respect this concept is just wrong. 73's JC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Adding chicken wire or mesh on top of radial field
the case for short radials or mesh wires. If you disconnect the 1/4 elevated wires from the feed line it does not work as well. The soil surface conductivity is vey low. If you think about a cooper plate large as a football field or salt water, a vertical near it will perform very poor, it only will perform well "on it" , connect with the plate and on top of the plate. That's way AA7JV vertical antennas works so well, George install them inside the water. Near the salt water does not work. Conductivity wet ground (beach) is 0.02, sea water 5. The same with radials and mesh wire if you don't connect it, it does not work! 73's N4IS JC -Original Message- From: Topband On Behalf Of Raymond Benny Sent: Monday, June 4, 2018 3:05 AM To: Peter Bertini Cc: 160 Subject: Re: Topband: Adding chicken wire or mesh on top of radial field Peter: Is this a question or what you are saying is a known fact? I am very interested in this outcome since I will a installing a TX 4SQ system where some existing ground radials. Over time, I have heard both pros and cons on this subject. I would like to read some research or documentation on this subject. Tnx, Ray, N6VR Near Prescott, AZ On Sun, Jun 3, 2018 at 1:14 PM, Peter Bertini wrote: > Why would bonding the added matting be required if it is laid over or > beneath an existing radial field? It reduces ground losses regardless. > > Peter > _ > Topband Reflector Archives - http://www.contesting.com/_topband > -- Ray, N6VR _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: How Increase 160m power on FL2100z
I owned a FT2100Z for several years and the power on 160m was the same as other bands. I don't expect any design flaw. The original tubes are not available anymore, the 572's tubes manufactures nowadays are different and optimized for audio applications and does not perform at the same level as the originals 572's. You may just need more drive or change the input circuit for 160m. Regards N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Crossed Field Antenna
This antenna was evaluated before and published in QEX May June 2005 Just google >> Broadcast CFA antenna 73's N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Guy Olinger K2AV Sent: Thursday, April 10, 2014 2:43 AM To: Bill Aycock Cc: Michael St. Angelo; TopBand List Subject: Re: Topband: Crossed Field Antenna Let's see, what was that term, "undead"? 73, Guy. On Wed, Apr 9, 2014 at 11:31 PM, Bill Aycock wrote: > WOW!! > I thought that had been shot with a silver bullet, at a crossroad, and > had a stake driven through its heart over ten years ago! > The Flat-Earthers are still among us. > Bill--W4BSG > > -Original Message- From: Michael St. Angelo > Sent: Wednesday, April 09, 2014 8:28 PM > To: topband@contesting.com > Subject: Topband: Crossed Field Antenna > > > It's been quiet on this group. > > The April 9th issue of Radio World Magazine has an article about the > Crossed field Antenna. > > An company, Crossed Field Antennas LTD, Has filed a comment with the > FCC espousing its advantages: > > <http://apps.fcc.gov/ecfs/comment/view?id=6017582994> > > This should rustle you from you winter doldrums.. > > 73, > > Mike N2MS > > _ > Topband Reflector Archives - http://www.contesting.com/_topband > _ > Topband Reflector Archives - http://www.contesting.com/_topband > _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Shunt feeding the Skyneedle - new developments
>> I'm sure it will play well in terms of keeping your transmitter happy but the relatively large bandwidth you are measuring is indicative of substantial loss in the system somewhere. This would be a large bandwidth even if you did not have the bandwidth narrowing effects of a shunt feed. << Hi guys, the 3 wires is actually a transmission line and the antenna is well known as Folded Unipole with 200 ohms impedance. My antenna is a Folded Unipole as well and has the same broadband SWR measurement's. The loss is the same for any tuning circuit it has nothing to do with the bandwidth. The ground plane does, and in this case it is the same, right? 73's JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Shared Apex Loop Array
Hi Jim >> The antenna geometry indicates that it should perform similar to a Waller Flag *under the same conditions*. << The perform under same conditions is expected, however the WF RDF is between 11.5db to 12 db. How that compares with a 8.5db RDF antenna? I would say two antennas with the same RDF should perform similar. The WF is a different antenna, it's a rotatable pair of loaded loops. Each loop is open and loaded with a resistor. Regards JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: circular polarization on 160m
James You brought a good article about HF propagation, however the behavor on 160m is different from HF. If you check on the KL7A arcticle figure 1 what is happening between 1 and 2 MHz you can see that the green and red does not behaivor the same way as above 2 MHz. This subject is more complex because there us no shirt answer, actualy between 1 and 2 MHz. the ionosphere does not support linear polariration wave. The wave are actualy eliptical and not circular for most directions. You can check the long answer on the "must read book" from NM7M . R Brown 'The Big Gun's Guied to Low Band Propagation" . Magneto-iomic Theory pag 47 to 56 ; and Power coupling pag 57. Thanks to Karl. K9LA, the book is available on his also must read site on the 160m link http://k9la.us/html/160m.html Regards JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: circular polarization on 160m
Tom '>> The way I see it is if the rate is not 0.546 uS or so, you do not have circular polarization.You have a slowly rotating wave, and the sense of the RX antenna would be meaningless unless you could time-sync rotation at that slow fading rate. Someone correct me if I am wrong. << 100% correct My system has two WF's, same gain, one vertical and another horizontal, feeding two preamps into IC7800 two receivers. When there is fading on the signal E-W, the time of the rotation from H to V could be long as 5 minutes, most of the time between 1 to 2 minutes. Using M=S on the IC7800 I can keep the two receivers at same frequency, and I can hear one receiver on each ear. I used to QSO Raoul ZS1REC during summer time and sometimes we start the QSO using V pol and finished on H pol.. About the signal noise gain using H and V with two identical receivers, I can say there is no gain at all, when the signal is weak, I switch the other antenna off and hear with only one channel. The advantage to have both is just to avoid listening in the wrong antenna listening on both antennas at the same time. It is not diversity eider because my antennas are only 60 ft. apart . Besides E-W when the signal is coming from less 45 degree and it is fading, I never see rotation, the vertical signal can have a deep QSB and the horizontal signal constant with no QSB. That just happened last Saturday with the FT5ZM, the horizontal signal was solid all the time with no variation on the intensity, however the vertical signal had deep and fast QSB. My take on that is the propagation mode or multi-path, signals can arrive from a refraction out of a duct and or from the same direction but from a different region on the ionosphere. There is no real correlation between the two polarizations signals, in practice they don't mix. It is very different from HF or VHF where the wave is always coming from the same media. Another point is that refraction increase with the decrease square of the in frequency, on 160m the refraction is stronger than 80 or up, as a result it is not necessary to transmit a horizontal signal to answer a horizontal polarized income signal. When the TX signal reach the first refraction point the wave split in two one vertical and another horizontal. What means is the efficiency to couple the TX signal with the atmosphere this is more important than the polarization itself, but 160m only, moving up in frequency the results are completely different, and 30 MHz to 50 MHz it is even special because it is transition from HF to VHF propagation mode. The experiments on 28 MHz does not apply to 1.8 MHz. Between 1 and 2 MHz , everything is different from HF or VHF Regards JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: circular polarization on 160m
Hi Carl and top-band lovers I would like to mention Chapter 7.6 as well, polarization matching, and also 7.7 Fading. I started developing my HWF early 2009 and I think there is no more to squeeze from it. Here some update in respect of polarization on 160m. It is a game!, vertical and horizontal field changes all the time, an elliptic can describe better the waves on 160m. My last HWF tuning gave me another 6-8 db improvement on the signal noise ratio. The HWF is really an "all directions noise cancelling antenna ( Va-Vb=0)", the goal is maximum attenuation on the vertical field an good directivity on the horizontal field. The takeoff angle is always the same and does not change with the height above ground ,it always very close to 40 degree. It is alike high horizontal dipole that takeoff change with the height from ground. The HWF has a deep null from high angle signals at any height above ground. The game is maximum attention on the vertical signal because most of the manmade noise, power line noise, city noise propagate with vertical polarization due the proximity with the ground for 160m waves. For 160m the HWF needs to be over 100 ft. to perform well on the horizontal signals, 50 ft. is ok for 80m and up. The HWF works 160m to 30m with excellent performance depending on the area of the loops. The HWF gain is around -43 db, and the vertical attenuation can be adjusted to deep another -50db, the total attenuation front and back is > -90 db , It has a front null and a back null for vertical signals. This is a weak, weak, weak signal system implementation, very complex by nature by receiving near the receiver noise floor most of the time. Depending on the direction of the wave the H/V ratio can be -20 db or more both ways, most of the time the vertical component is 10 to 20 db stronger than the horizontal component. When you combine the 4 variables, vertical gain, horizontal gain, vertical noise QRM and the signal H/V ratio you have your final signal to noise ratio, however on top of that you need to add the propagation noise as well. Another dependence is the solar cycle. We are at the peak of the solar cycle and the propagation this year has been very different . Long pass is peaking at the SS or SR and the signals from North are showing a strong horizontal component. or it could be just coincidence, just time will tell. Nowadays I can copy better weak signals with my HWV than my VWF in all directions. I just observed that recently with 8Q7BM, NH0Z,V63DX,4J6RO, 4K6FO and 4L5O, signals from NNW and NNE better on HWF. It is the first time I can hear better signals coming North with the HWF. It is all about signal noise ratio. For long path the new adjust also helped a lot. I detuned the TX tower to minimum noise on the HWF, making the diagram symmetrical on the polar plot. It looks like a butterfly for local vertical signals. Peter HS0ZKX is coming strong from SSW every 28 days. Just after the solstice last month the long path propagation was just fantastic. WV8. H40,RA0. JA. BA. BG and DU7 copy with Q5 from SSW from Dec 25th to Jan 1st , but few QSO's. only JA and DU7 on the log. FT5ZM only on the HWF as well. I agree with Carl. There hasn't been much work in polarization field on 160m, however It is a fascinate subject. Come on in folks! Regards JCarlos N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Luetzelschwab Sent: Monday, February 03, 2014 12:17 PM To: topband@contesting.com Subject: Topband: circular polarization on 160m I hope everyone has had a chance to work FT5ZM on topband. With respect to circular polarization on our HF bands (3.5 - 28 MHz) and on 6m, theory says both the ordinary and extraordinary waves propagate thru the ionosphere with pretty much equal ionospheric absorption. Thus circularly polarized antennas can provide an advantage. Some of the real-world examples I'm aware of have been documented by G2HCG on 10m (in the old Communications Quarterly), by the original K6CT on 20m (in the RSGB Bulletin) and by WA3WDR on 75m (a web paper). I'm sure there are others out there, too. On 160m, theory says the extraordinary wave incurs much more ionospheric absorption (more heavily attenuated) due to 1.8 MHz being so close to the electron-gyro frequency. Thus in theory only the ordinary wave is useful on 160m, which says circular polarization wouldn't do any good. Now things happen on 160m in the real-world that we simply don't understand. For example, an ordinary wave can excite an extraordinary wave under certain ionospheric conditions (if you'd like to read more, curl up in a warm place on a cold night with Chapter 3 in Ionospheric Radio by Kenneth Davies). Could this be happening? I don't think we can rule it out. In my opinion based on all the reports on this reflector over the years, it seems to me that having selectable elevation angles is more imp
Re: Topband: Compromise vertical loading questions
Hi Bjorn >>>>> How much I can improve by moving the coil up. What improvement should I expect if center loading at about 7 meter? How about moving the coil all the way up to the top loading spokes? Is it worth the effort? (the pole wont support much up there). .>>>>> Not much, changing the loading would increase the signal 5-10% , it is around 1 db, however if you can get close to salt water and get the radials wet your signal can increase 10db or more. AA7JV can comment better on that, but close to the water is not good, in the water is unbelievable better. George used get several wires tied with a stone and through it into the water, as you increase the number of the wires, you can see the impedance changing. You will may lose some of the radials and they need to be replaced. The radials could be very short and thin but they will work if in the water. I can hear you almost every day with the antenna you are using now. Regards JC N4IS _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Single antenna port xcvr but want to employ separate receive antenna
Hi James There are several solutions for a separated receive port. However let me comment on some details, 1- Small Delta loop. To be a receiver antenna the antenna gain need to be less than 20 db, why ? simple. Connect a power meter and a 50 ohms load on the Small Delta loop and measure how much power is captured from the TX antenna, I know several guy the burn the RX port on ICOM and YAESU radios using transmit antennas as receiver and injecting 100W into the RX port when transmitting with a legal limit amplifier. Port isolation and RF protection must be the first concern for any solution. If the antenna used for RX is resonant on the same TX band , you can really burn you RX front end. 2- Switch speed. The receive port need to switch fast than TX port. 20ms is not enough, most small frame relays switch around 20ms , To play safe it is necessary < 10 ms. Another thing to consider. 3- The RX antenna only will add some SN if it adds some directivity, otherwise the attenuator at -20db will do the same job. 4- Isolation, on low bands if you have s9+10db noise and only 50 db isolation between the RX and TX port, the signal from the TX antenna will be add to you RX signal degrading the signal to noise and reducing side and back nulls form the RX antenna. I can list another several reason to the subject but the T/R switch is a very important part of the receiver system if you want to have some improvement on the signal noise. I sent one RTR-1 to T6LG to use with a good Preamp from KD9SV and a Delta Flag antenna using twisted pair. Without the RTR-1 the system would not perform well as it did. Just my two cents. Regards JC N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of James Rodenkirch Sent: Monday, January 13, 2014 8:36 AM To: Top Band Contesting Subject: Topband: Single antenna port xcvr but want to employ separate receive antenna Have my vertical working great and have a small Delta-loop low band receive antenna BUT the Ten Tec Jupiter doesn't have a separate receive antenna like a K2, for instance (I borrowed a K2 to try out but the buttons/controls are to small for me to operate as I have a severe case of peripheral neuropathy, courtesy of Agent Orange).So, I am up and running and will be in the CQ 160 contest at the end of January but have no means, currently, of switching rapidly 'tween the top loaded vertical and loop. A T/R switch won't "do it" for meso looking at a DX Engineering RTR-1A but sure don't like the price!!http://www.dxengineering.com/parts/dxe-rtr-1a Anyone have an RTR-1 or 1A that is excess to their needs and willing to sell OR have another idea of how I can employ a separate receive antenna when I have one antenna port? Thank you, in advance, for any repliesoff line replies work for me. 72/73, Jim Rodenkirch K9JWV _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Digital mode spurious issues
Tom, Mike is right, the issue with audio overload is complex for most of new radios, most of them have A/D just at the MIC input, if the A/D overloads the RF chain is compromised. These radios have no actual filters, everything is digital, like the IC7600. An analog radio is BW limited by the SSB crystal filter but SDR don't, when the A/D overloads, there are spoors everywhere several KHz far from the carrier; enough to trash the entire band. Using a SDR water fall it is easy to see the signal transitions and associate the trash with the main signal. I've seen several spoors every 10 KHz almost 100KHz up and down 1838. This is a growing problem. 73, JC N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Mike Waters Sent: Monday, December 30, 2013 1:31 PM To: Tom W8JI Cc: Topband Subject: Re: Topband: Digital mode spurious issues Tom, I believe the mode that operates at 1873-1838 is JT65, and WSJT is needed to decode it. I never tried it. It was developed by K1JT for weak-signal and EME work. http://www.physics.princeton.edu/pulsar/K1JT/wsjt.html A common scenario with digital modes is that the audio into the mic input is too high, causing unwanted spurs. 73, Mike www.w0btu.com On Mon, Dec 30, 2013 at 11:11 AM, Tom W8JI wrote: > ... a digimode station up roughly around 1837 came on with a LSB > "spurious" signal on 1833. His signal was a series of slowly changing > stepped tones. I don't know what mode that was. His unwanted sideband > suppression was about 40 dB, but that was not nearly enough. He was 15 > dB out of noise with his unwanted sideband. > > Does anyone know of a universal software to decode signals? Since the > FCC does not require a CW ID, I think that is the only way to identify > stations. ... > _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: FW: Steady Carrier on 80 CW
I just checked 3501.6 and I have no copy or trace during daytime. I'm confirming the 350 degree direction from Ft Lauderdale JC 73's N4IS _ Topband Reflector
Re: Topband: Steady Carrier on 80 CW
Hi guys I'm in Ft Lauderdale EL96ub and the carrier on 3501.6 is s9+10 coming around 350 degree with some QSB. Regards JC N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Don Kirk Sent: Saturday, November 02, 2013 9:29 PM To: Tom W8JI Cc: Charlie Cunningham; topband Subject: Re: Topband: Steady Carrier on 80 CW Hi Guys, K5ESW reported the following : The 3501.5 carrier is audible in daylight in Raleigh, NC. It is running > S3-S4 now at 3 pm local. It was about S6-S7 or better at night. What would be interesting to know is if anyone can hear this signal 24 hours a day, and then DF activity should be done from that area during the middle of the day. I will ask K5ESW if he can still hear this signal between noon and 3pm. In the Indianapolis area the signal runs S7 to S9 on my TX antenna during hours of darkness, but lots of fade/multipath. I noticed the signal was much more stable in the late afternoon (still light outside and running S&) when I first heard it today (probably less multipath), and therefore tomorrow afternoon when it first appears I will attempt to update my headings. Don On Sat, Nov 2, 2013 at 9:10 PM, Tom W8JI wrote: > Based on Tom's bearing, the source is clearly not in the Carolinas as > a few >> have specuilated. >> >> Charlie, K4OTV >> > > You can be absolutely sure it is not in or anywhere near NC. > > My heading can't be more than a few degrees off. This closely matches > Jerry's line, his line is just west of mine and almost parallel. > > The only issue is the multipath the signal had near sunset, but I > think I got a pretty good average at 130 degrees true from me. (EM73XB or EM73XC). > A second reading later in time is always best to double check, but the > signal went away. > > > 73 Tom > _ > Topband Reflector > _ Topband Reflector _ Topband Reflector
Re: Topband: Beverage antenna terminations
Bruce I lost several resistors on my WF until I started to use NTE 3 W Metal on the vertical Waller Flag and on the Horizontal WF I am using an array of 9 parallel/series. http://www.nteinc.com/resistor_web/pdf/threew.pdf Since that I never replaced it a single time in the last 4 years. The resistor has very low inductance but it is hard to find it, average price is near U$1. http://www.sourceresearch.com/store1/quickstore.cfm?ProductID=48700&do=detai l Regards JCarlos N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bruce Sent: Tuesday, September 24, 2013 10:46 PM To: Tom W8JI; topband@contesting.com Subject: Re: Topband: Beverage antenna terminations They were supposed to be non-inductive carbon, but need to find something better like carbon film. - Original Message - From: "Tom W8JI" To: "Bruce" ; Sent: Tuesday, September 24, 2013 2:55 PM Subject: Re: Topband: Beverage antenna terminations > What kind of resistors are you using? > > They shouldn't do that if you use the right type. > > - Original Message - > From: "Bruce" > To: > Sent: Tuesday, September 24, 2013 8:50 PM > Subject: Topband: Beverage antenna terminations > > >> After recent night time thunder storm activity, two Beverage antennas >> lost some directivity. Termination resistors looked normal, but an >> ohmmeter checked reviled they had each gone >> hundreds of ohms higher. Replaced resistors and back to normal. >> >> 73 >> Bruce-K1FZ >> www.qsl.net/k1fz/bogantennanotes/index.html >> >> >> >> _ >> Topband Reflector >> >> >> - >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2014.0.4117 / Virus Database: 3604/6694 - Release Date: 09/24/13 >> > > _ > Topband Reflector > _ Topband Reflector _ Topband Reflector
Re: Topband: WLW
Here is the K7AGE posts video of WLW's 1932 500,000 Watt AM transmitter http://forums.qrz.com/showthread.php?398944-K7AGE-posts-video-of-WLW-s-1932- 500-000-Watt-AM-transmitter Enjoy it Regards JC N4IS _ Topband Reflector
Re: Topband: 3B9EME
That's just pure propagation, 160m duct is the most common mode for most DX. 3B9 was peaking 599 in Texas and 589 in KP2. The signal was just not getting down here in South Florida due Es clouds. The expedition is doing a great job starting on 160m at SS and sticking past SR even with a very low QSO rate. Tomorrow is another day, maybe it will be our turn. Regards JCarlos N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Dave Novoa W4DN Sent: Monday, September 09, 2013 10:41 PM To: topband Subject: Re: Topband: 3B9EME This DXpedition has not been particularly strong on any band, specially here in South Florida. Their vertical for the low bands may not be working well, plus they do not mention any receiving antenna on 80 or 160 on their web page (www. ari.verona.it/veronadxteam/3b9_2013.htm ). 73, Dave _ Topband Reflector _ Topband Reflector
Re: Topband: CAT5 for Flag Antenna Feedline ?
Bob Here the missing part of my original post to motivate you to try a single twisted pair. See bellow Ilian's comments about the performance of the RX antenna. Illian was not detuning his TX antenna. Regards JC N4IS hi Jose [12:02:50 PM] Ilian: My log is already uploaded on LoTW and ClubLog [12:03:23 PM] Ilian: 1394 QSO on 160m [12:04:15 PM] Ilian: more than 1200 QSOs after RX antenna installing [12:05:02 PM] Ilian: about 150 QSOs without RX antenna for more than 2 months on the air [12:05:57 PM] Ilian: 1200 QSOs made with RX antenna for 1 month and 10 days [12:06:49 PM] Ilian: 68 DXCC worked on 160m during the all operation [12:07:49 PM] Ilian: about 40 countries worked after RX antenna installing within 1 month and 10 days [12:09:49 PM] Ilian: 3865 QSOs on 80m during the all operation, about 2500 worked after RX antenna installing [12:10:24 PM] Ilian: 112 DXCC worked on 80m for whole period [12:11:54 PM] Ilian: about 50 new DXCC worked after RX antenna installing for a month and 10 days [12:13:36 PM] Ilian: http://t6lg.com/?page_id=221 [12:14:05 PM] Ilian: you can see all statistics here [12:15:57 PM] Ilian: Thank you, Jose! -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bob K6UJ Sent: Monday, September 09, 2013 10:20 AM To: topband List List Subject: Re: Topband: CAT5 for Flag Antenna Feedline ? Jim, Your hams guide to RFI is my bible for mitigating RFI issues. My feedline chokes are all designed from this great article. I probably have optimized my feedline to the flag in regards to common mode noise but after reading the post I was curious about CAT5. Before possibly wasting my time experimenting with CAT5 for feeding my flag I wanted to learn more about it. Below is a paragraph from the Topband reflector thread titled "high performance receive antenna at T6LG" that sparked my interest. They were discussing the delta shaped flag they used which was used before on the FO0AAA dxpedition. Bob K6UJ The parts for the antenna was very simple, a 9"1 balun and a 910 ohms resistor, and a 100 to 75 ohms BALUN to feed the preamp. The key component here was the CAT 5 single twisted pair to feed the flag antenna without any common mode noise pickup (it is necessary to strip the CAT5 and separate each of the 4 pairs), a coax cable won't work in high noise environment, even with a killer choke the ground does not help to stop the common node noise. That was not the first time a twisted pair saved the day, two years ago I suggested Rolf PY1RO a similar antenna fed with twisted pair that worked very well, bringing the noise to zero in a s9+20 noise environment. On Sep 8, 2013, at 11:12 PM, Jim Brown wrote: > On 9/8/2013 10:30 PM, Bob K6UJ wrote: >> I got the impression from the post >> that CAT5 is immune to common mode noise. > > I've not heard that, nor can I think of a theoretical basis for saying so. CAT5 is very good twisted pair, with a high twist ratio, Zo = 100 ohms, and its loss is low enough to make it work fine on 160M. The primary advantage of twisted pair is that it rejects DIFFERENTIAL mode noise. Rejection is greatest when both ends of the line are balanced. > > One possible source of your confusion may be reading, but not fully understanding, my work, and Neil Muncy's work, on SCIN, whereby certain deficiencies in the construction of a cable shield convert common mode current to a differential voltage on the signal pair. I have on several occasions observed that high quality unshielded twisted pair, like CAT5/6/7, would have much better noise rejection than that sort of cable. Read about it in several tech papers and tutorials on my website. No need to burden the list with it. > > 73, Jim K9YC > > _ > Topband Reflector _ Topband Reflector _ Topband Reflector
Re: Topband: How to detune a wire Inverted L? How to 'detune'electrical fence
Tim The issue with the relay at the antenna is the time to close the contacts and avoid RF hot switch. I'm using a Jennings RJ1A-26S for years, just 4-6 milliseconds to close. Or you can use a sequencer, or a winkey2 with cw lead time and PTT2 for the amplifier. http://www.mgs4u.com/RF-Microwave/vacuum-relays-SPDT.htm Regards Carlos N4IS _ Topband Reflector
Re: Topband: Zo of an individual CAT5 twisted pair
Yes, that's a complicated matter. The name and the function can get very confused if you don't know what you are doing. Any transformer can change the voltage from the primary to the secondary and the impedance follow the square of turn ratio. How you connect the transformer is an application. How you build the transformer is an art! For broadband RX antennas you want the transformer to be broadband. For isolation from the primary to the secondary you want low capacitance. An autotransformer could be used as BALUN, balances input and unbalanced output, it could be broadband, but has no isolation. One example, you take a FT140-77 core and build a primary 12 turns in one side and 4 turns on the other side, you have a voltage transformer but it will perform very bad as a BALUN, or a BALBAL or UNUN depending your application. However if you build 3 times 4 turns for the primary and add 4 turns on secondary in between the primary, you can get the same voltage transformer but It will work as a broadband impedance transformer from 1 MHz to 10 MHz with no adding reactance if the load is a pure resistor or low inductance resistor. I did try to explain it with text, I used pictures, I posted diagrams but people come back to me saying the antenna is not working. When I check what the guy did, he was using the wrong "transformer". Jim I'm with you again, very few hams really understand it. Regards JCarlos N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Shoppa, Tim Sent: Tuesday, August 13, 2013 8:08 AM To: 'j...@audiosystemsgroup.com'; 'topband@contesting.com' Subject: Re: Topband: Zo of an individual CAT5 twisted pair A transformer that is connected such that it is UNbalanced on one side and BALanced on the other, and connected that way on purpose, is not a balun? Tim N3QE - Original Message - From: Jim Brown [mailto:j...@audiosystemsgroup.com] Sent: Tuesday, August 13, 2013 03:16 AM To: topband@contesting.com Subject: Re: Topband: Zo of an individual CAT5 twisted pair On 8/12/2013 2:10 PM, JC N4IS wrote: > 50/75 BALUN Thanks for the detailed post, Carlos. BUT -- please let's use the right words to describe things so that people understand what you're describing and how it works. I strongly suspect that at least some of those things you are calling a "balun" are really a simple transformer -- that is, a primary and a secondary with magnetic coupling between them, and probably on a ferrite or powdered iron core. If it's a transformer, let's call it a transformer. Likewise, if we have a common mode choke formed by winding a coil of the transmission line, it is a common mode choke, not a "balun." Using the word "balun" confuses things, because that word is used to describe at least a dozen very different things that I know of. When we use the word "balun," it's a magic box that few hams really understand. When we use the right word, most hams have a chance of understanding what it does in a circuit. :) Yes, there are arrays of common mode chokes that can be used to transform impedance, and there are transmission line transformers of various sorts that can do that as well. BTW -- your discussion of phasing between elements of an RX array causes me to add an important post script to my advice that a perfect match is not required. When ANY passive network is used to produce phase shift, the source and termination impedances DO matter. The tricky part, though, is knowing what the input Z of the RX is, and if you're doing something like a phased array using phasing lines that end at the RX input, it might be a good idea to actually measure input Z and the antenna Zs with a VNA. 73, Jim K9YC _ Topband Reflector _ Topband Reflector _ Topband Reflector
Re: Topband: Zo of an individual CAT5 twisted pair
Well, Jim, here is what N4IS stated (bolded words my emphasis) - > > looks like he found the twisted pair to reduce the noise > Yes, but there's a bit more to it. Twisted pair, by its nature, > minimizes noise pickup. That rejection is maximized if the > terminations at both ends of the line are balanced -- that is, each > side of the line has equal impedance to ground -- and if there is > minimal common mode coupling at each end Hi guys Jim is 100% right, balancing both ends is a MUST. But there is more. I would like to share what happened few month ago with a WF project. Peter N8PR built a beautiful WF with a polarization rotator. Peter can turn his WF horizontal or vertical. Very nice project. We decided to check the phase when the WF was about to go up. I measured the phase using a oscilloscope driving the feed line input with 5W to measure the phase at the loops. First at the 9:1 BALUN that feed the loops, the phase was correct and near 180 degree, but the amplitude was not the same between the two loops, let's say 10% different from each other. Then when I measured the phase at the resistors, the phase was very different between them, near 50 degree and the amplitude way off, like 50% difference. It was hard to understand why such difference between the two loops and even harder to understand the phase difference between the transformer and the resistor in the same loop. After removing all BALUNS and measuring them at the bench with a VNA we found one isolation BALUN inverted. Peter was feeding his WF with 75 ohm, and the BALUN had 4 turns on the 50ohms side and 5 turns on 75 ohms, and it was connected backward, 4 turns to the 75 ohms and 5 turns to the 50 ohm point, where the two 100 ohms line are connected 180 degree. After connecting the BALUN the way it should be, the phase measured at the transformer and the resistor become equal in both loops, and the amplitude also was equal as expected, the difference in phase or amplitude was not detectable anymore. It was the first time I faced this situation. The FLAG antenna, or EWE, K9AY , pennant and WF are actually a loaded loop. Adding one resistor inside the loop the gain drops but you get a cardioid pattern, good front back and good RDF. The signal when reach the first vertical wire is reflected to the second wire, and the signal when reach the second wire the signal is reflected to the first wire. When the signal reach the resistor it is dissipated, and when the second signal reach the transformer it goes to the feed line. The combination of these two currents give us the cardioid pattern. In the WF there is a combination of two cardioids to get side nulls and higher RDF. All this work fine "IF" there is no mismatch when the signal current reach the resistor and the BALUN, any mismatch impedance inside the loop will change the phase, and as a result, a deterioration in directivity. The value of the resistor should be very close to the impedance at the transformer, Example, for a FLAG feed with100 ohm line and 9:1 BALUM giving 900 ohms impedance, the resistor should be near 900 ohms to avoid SWR inside the loops. This is necessary to keep the right phase to form a cardioid pattern. The FLAG is no resonant an can be used from 1Mhz to 10 MHz, BUT it is very sensitive to impedance mismatch. Before correcting the 50/75 BALUN the SWR measured with a MFJ was near 1;1,8. After correcting the BALUN it was 1:1,5. Measuring only the SWR does not tell much about the antenna. The FLAG wants to work, like Luis once said. However if there is a mismatch anywhere the results won't be good. It is complicated to measure impedance on 160m, near AM signals around. The FLAG or dual FLAG like the WF require a perfect match to provide the expected performance, and any common mode current can compromise the RDF and the overall performance. Do It right at the first time, don't change anything in the project! Use what was recommended. Regards JCarlos N4IS _ Topband Reflector
Re: Topband: best core material?
If you plan to use the antenna on 160m you'll need 73 material. 43 works 3.8 up. Regards JC N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of James Rodenkirch Sent: Monday, August 05, 2013 2:20 PM To: Shoppa, Tim; BY THE LAKE; topband@contesting.com Subject: Re: Topband: best core material? I wasn't going to use a binocular core, Tim - I was going to use the Amidon FT-140-43 OR the FT-140-77 IF it made any noticeable differenceis there some magical reason to use binocular vice standard "round"? > From: tsho...@wmata.com > To: rodenkirch_...@msn.com; ma...@isp.ca; topband@contesting.com > Subject: RE: Topband: best core material? > Date: Mon, 5 Aug 2013 18:12:48 + > > If receive only, you will do just fine using the 2873000202 binocular 73 material core that Tom mentions. > > I think this corresponds to Amidon part number BN-202-73. Newark stocks the part under the original Fair-Rite 2873000202 number. > > Tom shows 2:5 ratio but I've done other ratios just fine. > > I am very very impressed with the 2873000202 core, in fact I also use > it in some DC-DC converters and the core just barely gets warm at the > 10 watt level. Whenever I've accidentally transmitted into my receive > antenna, the transformer survives just fine, it's the terminating > resistor that goes up in smoke. I try not to make a habit of it :-) > > Tim N3QE > > -Original Message- > From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of > James Rodenkirch > Sent: Monday, August 05, 2013 2:04 PM > To: BY THE LAKE; topband@contesting.com > Subject: Re: Topband: best core material? > > Sorry - didn't make it crystal clear that this is a Delta shaped variant of a EWE antenna > > My bad for not utilizing all of the necessary verbiage to make that clearyou see it in ON4UN's latest book on page 7-104. > > > > > > From: ma...@isp.ca > > To: rodenkirch_...@msn.com > > Subject: Re: Topband: best core material? > > Date: Mon, 5 Aug 2013 14:00:48 -0400 > > > > A full-wave delta loop would have the transformation done with a 1/4 > > wave line of 75 ohm cable. This must be something other than a full-wave loop? > > > > Bill VE3NH > > - Original Message - > > From: "James Rodenkirch" > > To: > > Sent: Monday, August 05, 2013 1:33 PM > > Subject: Topband: best core material? > > > > > > > > > > I have a schematic for a delta shaped loop that shows I'll need an > > > 18:1 transformer to transform the 950 ohms of the antenna to 50 > > > ohms (feeding it with 50 ohm coax). > > > > > > One transformer diagram shows an FT-140-43 core being used. > > > > > > BUT, looking over some of Tom's, W8JI, write-ups, I see where he > > > uses 73 material instead. > > > > > > I see where 77 material replaced 73 material so -- is an FT-140-77 > > > the mo betta way to go? > > > > > > > > > Thanks, in advance, for any advice/info. Jim Rodenkirch K9JWV > > > > > > > > > > > > _ > > > Topband Reflector > > > > > > > > > - > > > No virus found in this message. > > > Checked by AVG - www.avg.com > > > Version: 2013.0.3392 / Virus Database: 3209/6552 - Release Date: > > > 08/05/13 > > > > > > > > > > > - > > No virus found in this message. > > Checked by AVG - www.avg.com > > Version: 2013.0.3392 / Virus Database: 3209/6552 - Release Date: > > 08/05/13 > > > > _ > Topband Reflector _ Topband Reflector _ Topband Reflector
Re: Topband: High performance RX antenna at T6LG
Hi Arunas >>> I just wondering what is the reason to separate each of CAT5 pairs? <<< The main problem in high noise environment is common mode noise, The unused wires does not help to eliminate common mode noise. Actually the unused pairs will deteriorate common mode isolation, The gain on the flag could be -35db and a high gain preamp is necessary. There is another reason, the unused pair can become an antenna too, and interact with the vertical part of the flag. Check also the cross talk on CAT 6 or CAT 5 it is not that great. The 100 ohms impedance is excellent, and one single pair is very light., does not load the flag, in special horizontal flags or square loops. I had no success trying to use one cat 5 with a low gain antenna in one end and a high gain preamp on the other end, However I think it is possible to use all pairs if the preamp is located near the flag, driving current into the cable, and the common mode noise killed by chokes at both ends. I do not recommend using the cable without stripping the pair you want to use under high noise environments. Regards JC N4IS _ Topband Reflector
Topband: High performance RX antenna at T6LG
Hi Top-banders I just got this skype IM for Ilian T6LG and I would like to congratulate Ilian for his dedication on all aspects of Ham radio. hi Jose [12:02:50 PM] Ilian: My log is already uploaded on LoTW and ClubLog [12:03:23 PM] Ilian: 1394 QSO on 160m [12:04:15 PM] Ilian: more than 1200 QSOs after RX antenna installing [12:05:02 PM] Ilian: about 150 QSOs without RX antenna for more than 2 months on the air [12:05:57 PM] Ilian: 1200 QSOs made with RX antenna for 1 month and 10 days [12:06:49 PM] Ilian: 68 DXCC worked on 160m during the all operation [12:07:49 PM] Ilian: about 40 countries worked after RX antenna installing within 1 month and 10 days [12:09:49 PM] Ilian: 3865 QSOs on 80m during the all operation, about 2500 worked after RX antenna installing [12:10:24 PM] Ilian: 112 DXCC worked on 80m for whole period [12:11:54 PM] Ilian: about 50 new DXCC worked after RX antenna installing for a month and 10 days [12:13:36 PM] Ilian: http://t6lg.com/?page_id=221 [12:14:05 PM] Ilian: you can see all statistics here [12:15:57 PM] Ilian: Thank you, Jose! Here a little tail about this high performance RX antenna. Ilian was operation in a military campus, you can see the pictures on his website www.t6lg.com The noise level was unbearable for low bands, Ilian was not able to hear even the strong European station but Ilian had a good signal on low bands. I worked him on 80m back in October and start chatting with him on skype. I proposed a flag antenna to improve his RX capabilities. The problem with most field station is lack of good ground, this issue makes a very complicated situation with common mode noise everywhere, from the coax cable feeding the inverted V to the AC wire system and power generators, and other antenna cables. There is not a simple way to ground the receiver, every wire connected to the radio became part of the antenna system. The solution was a system , not only a simple flag antenna. Ilian radio is a FT897 that does not have a separated RX port. I send him a DX Engineering RTR-1 Receive Antenna Interfaces RTR-1, that switch was necessary to keep high isolation between the RX antenna and the TX antenna. The flag antenna has low gain and I sent Ilian a preamp made by Gary KD9SV, a FET follower design with high IP3. The parts for the antenna was very simple, a 9"1 balun and a 910 ohms resistor, and a 100 to 75 ohms BALUN to feed the preamp. The key component here was the CAT 5 single twisted pair to feed the flag antenna without any common mode noise pickup (it is necessary to strip the CAT5 and separate each of the 4 pairs), a coax cable won't work in high noise environment, even with a killer choke the ground does not help to stop the common node noise. That was not the first time a twisted pair saved the day, two years ago I suggested Rolf PY1RO a similar antenna fed with twisted pair that worked very well, bringing the noise to zero in a s9+20 noise environment. The Delta Flag antenna built by Ilian was very similar the RX antenna used by FO0AAA and described by K6SE. It is a triangle antenna (any size works) with 24 ft base and hung from a single point that allows Ilian to rotate the antenna. Actually this feature was very desired, Bill W4ZV educated Ilian about long path propagation on 80m and he made several very happy campus on West Coast listening South for Long Path on 80m. This antenna can be used on most of DX expeditions with no place for beverages, a simple RX antenna made with CAT5 wire can be a high performance antenna and a difference between no or few QSO's and few thousand QSO;s A single flag is not the best antenna you can build, the RDF is modest but the secret is how to implement this antenna avoiding common mode noise, a simple CAT 5 twisted pair can make a huge difference. I see no reason for a DX expedition to complain about noise on low bands, CAT 5 can be found anywhere and it is vey light. P.S. I was not able to work Ilian on top band, never had the spotlight. Regards Jose Carlos N4IS Delta RX Antenna used by FO0AAA from Earl, K6SE on June 1, 2000 View comments about this article! Several subcribers inquired about the Delta 160-meter receiving antenna used at FO0AAA. It is a close relative of the Pennant and Flag antennas, which are ground-independent relatives of the Ewe. The Delta is a modification of the "delta-shaped Ewe loop" shown in figure 7-66 on page 7-51 of ON4UN's new Low-Band DXing book. I took John's Delta-Ewe and, with the feedpoint and termination located at the bottom corners of the triangle, I used EZNEC to optimize the design for best F/B and zero reactance at 1.830 mHz. This is the design that was built by ON4UN for use by FO0AAA. It is a delta loop-shaped antenna with a 28-foot (8.537m) bottom horizontal wire and the apex 17 feet (5.183m) above the bottom wire. That
Re: Topband: alternative to vacuum variables
Pete Smith N4ZR wrote: > One of the reasons I have mot gone to high power on 160 is the cost of > capacitors for my omega match - at least $300. Anyone know of any > workable alternative? I remember someone writing about using > coiled-up RG-8, RG-213 or maybe Teflon coax. Where can I find more information? Yes, there is a great solution, I'm using it for almost 10 years. The issue with capacitors in 160m is the dielectric an most capacitors get hot and change the capacitance. I used 19 x 62 pFNPO 3KV capacitor to get 1200pF. Never had a failure. Just keep them apart , don't let two capacitor touch each other. Just put them in parallel. You can us a receiver variable capacitor to find the valor necessary to tune the antenna, then measure it and replace with X 62pF in parallel. I used PTFE tape for pipes tread to protect the packet from the weather. Capacitor, ceramic. 62pF 3,000V. CERA-MITE 564CC0GAA302EL620J You can find it in several stores, here the price is U$ 1 each http://www.electronicsurplus.com/Item/15444/CERA-MITE%20-%20Capacitor_%20cer amic_%2062pF%203_000V_%20-%20564CC0GAA302EL620J/ Regards Jose Carlos N4IS _ Topband Reflector
Re: Topband: DX window
Art >> A DL wondered how many DX can coexist in 5kHz. Not many. << I think 5 KHz can hold a lot of DX , CW and 100 Hz BW can do miracles, however just one local CQ machine gun calling CQ stopping only 2.5 sec can kill the same 5 KHz in the whole state. Regards JC N4IS ___ Topband reflector - topband@contesting.com
Re: Topband: DX window
Gary You have a god point, if we don't care they don't mind. I think we cc download the RBN file with all callers on the DX window during the contest, it is available in .csv, easy to filter using excel and send a formal complain to ARRL contest managers, It is not necessary to publish that list because is available for everybody download. Let see the ARRL reaction. If we don't protect the DX windows, we can't complain because we are gentlemen's and we made possible the gentlemen's band throughout the years and it was not staying aside the line and just watching. Any comments or actions? Regards JC ___ Topband reflector - topband@contesting.com
Re: Topband: one- way propagation
Here some interesting paper about LF MF polarization http://www.ann-geophys.net/22/1705/2004/angeo-22-1705-2004.pdf This paper, High-latitude propagation studies using a meridional chain of LF/MF/HF receivers >> Fig. 5. (a) Polarization of 50-5000 kHz signals recorded at Churchill, Manitoba, on 1-2 October 1997. White pixels indicate left-hand polarization, black pixels indicate right-hand polarization, and gray pixels indicate indeterminant polarization. (b) Power spectral density of the same 50-5000 kHz signals. Received signals above 1MHz are predominantly left-hand polarized except in the interval 09:00-12:00UT, 1-4 h before sunrise, when righthand waves dominate at frequencies above about 3Mhz. >> Figure 5 shows a possibly related effect occuring near the dawn terminator but involving wave polarization. The bottom panel shows a spectrogram of 50-5000 kHz signals recorded at Churchill, Manitoba, for 20 h, starting at 20:00 UT on 1 October 1997, a geomagnetically quiet day for which the signals show the usual diurnal pattern. >> 7'3 N4IS JC ___ Topband reflector - topband@contesting.com
Re: Topband: one- way propagation
Doug > Nope, Nope. I am a firm believer in one-way propagation on 160m, having witnessed it many times. > Can we agree, that we disagree.? When the signal is going up the polarization does not matter because after the first refraction the signal become elliptical, that's why the DX station independent of the polarization of the signal arriving here , always can copy me. I also witnessed many times the DX signal arriving only horizontal, including signals from. If the DX signal is arriving horizontal you won't be able to copy using your 4 SQ. even a high dipole does not do it because the dipole has no directivity, The RDF is very low, a dipole is not a receiver antenna. The fact you can't copy the signal does not mean that it is not there. It is special true for LP when I can copy signals very strong on the horizontal WV via SSW and not a single beep on the vertical HF, During the last 2 season I worked XU7ACY on 160m over 15 times (logging a QSO) ,and heard him way over 60 times, only with horizontal polarization. Same thing happened several times with Bobby VK3ZL, and it is not the local noise level. 73's JC N4IS ___ Topband reflector - topband@contesting.com
Re: Topband: one-way propagation
Jim > Is your WF horizontal antenna much higher than the vertical? < Yes, the HWF boom is at 116ft and the VWF=BWF as I used to call it , the boon is at 50ft Both antennas has RDF of 11.5 db, the HWF has 44 ft boom and the VWF has 50 ft, but almos the same negative gain, and high F/B and F/S the same too. The HWF has two horizontal loops cancelling each other, end feed, as a result the takeoff angle is 36 degree and there is a deep null from signals coming from the side and from 90 degree, same as F/S for the vertical WF(VWF). Regards JC -Original Message- From: N4IS [mailto:n...@comcast.net] Sent: Tuesday, December 04, 2012 6:18 PM To: jbw...@comcast.net; 'Tom W8JI'; topband@contesting.com Subject: RE: Topband: one-way propagation Jim Not always, polarization plays a lot on 160m, in special W-E E-W. Sometimes a signal from Africa dive on the QSB and disappear from the Vertical WF and switching to the horizontal WF the signal is peaking, other times I only can hear the DX signal horizontal. I don't call this unidirectional because I use a vertical TX all the time and the DX hears me well even the signal is arriving horizontal. Regards Jose Carlos N4IS -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of James Wolf Sent: Tuesday, December 04, 2012 3:41 PM To: 'Tom W8JI'; topband@contesting.com Subject: Re: Topband: one-way propagation Tom, It is a known that the ionosphere is not a perfect sphere. It is always moving and it is lumpy and tilted. Together these occurrences can cause focusing and defocusing of the wave due to deformities especially if they are concave or convex. One-way-propagation can reveal itself as a deep and/or prolonged fade on only one end of the link because of the aforementioned reasons.Of course fades can be caused by other reasons, such as multiple paths, etc. Jim, KR9U -Original Message- From: Tom W8JI [mailto:w...@w8ji.com] Sent: Tuesday, December 04, 2012 6:45 AM To: jbw...@comcast.net; topband@contesting.com Subject: Re: Topband: one-way propagation > To expand a little on Carl's explanation, the ionosphere is not as > isotropy as we commonly imagine - in that it is not a nice smooth > balloon shaped surface to bounce a signal off of. Instead, there are > varying degrees of irregularity, not unlike a sandy desert where the > wind moves the landscape around and creates moving peaks and valleys. > So imagine the ionosphere in this condition when a signal from one > direction has a nice reflection down to the receiver, but in the other > direction, it is reflected at a different angle and lands somewhere else. > > Jim, KR9U > There is no possible combination of refractions or reflections that is not reciprocal in both directions. If there is a mechanism at work, it is at an entirely different level than simple multiple reflections. After 50 years on 160, I'm still unsure if one way propagation exists. All of the "one way" I have seen and taken the time to look at involves noise levels, QRM, or just the capability of the stations. For example, prior to sunset here my local noise is very low. Even on a quiet winter night in a quiet direction, noise floor increases 10-15 dB as it gets darker and conditions improve. I can hear Europeans that I have no hope of working (on 40 meters this happens all day long). Their noise is high (even in a quiet location) because it is dark. As it gets darker their signals come up, and so does my noise and QRM, but eventually they hear me. The opposite occurs at sunrise. There is the same noise floor drop after daylight. This means I can hear JA's working west coast stations long after they stop being able to hear me. Local storms and local QRM, and the direction of that stuff, is also is a huge factor in reciprocity. Sorting it all out is very complicated, and involves far more than observing "sometimes people at one end don't answer". Sorting it out would involve and **require** calibrated observations of absolute signal levels and noise levels at both ends. I think this is why one way prop is, at best, arguable. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
