Re: Topband: 160M CQ WW SSB this weekend - Frequencies
Hi Mike! If this year is like other years, 160m will be filled from one band edge to the other. Yes, the lower half will have more stations operating than the upper half. 73 Lloyd - N9LB On Fri, Feb 27, 2015 at 1:03 PM, Mike Waters wrote: Can anyone suggest the best freqs. to tune our 160m inverted-L for the CQ WW SSB contest this weekend? The antenna is a long way from the house, andt's tough to do that in the pitch dark and cold. :-) It seems to me that in the past, it's been about where the CW contests always take place, and mine is now tuned for 1810 to 1850 or so. Is that OK as it is now, or should I move it up? www.cq160.com/rules.htm Thanks. 73, Mike www.w0btu.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 QSO K1N
ATNO = All Time New One Never worked Navassa on any band or mode. -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Jorge Diez - CX6VM Sent: Saturday, February 14, 2015 2:08 PM To: 'TopBand List' Subject: Re: Topband: 160 QSO K1N Hello anyone know if the removed 160 mts antenna? Nothing last night, so I think tonight will be no 160 mts, right? PD: what's the difference between ATNO and New One 73, Jorge CX6VM/CW5W -Mensaje original- De: Topband [mailto:topband-boun...@contesting.com] En nombre de Bob Cutter via Topband Enviado el: sábado, 14 de febrero de 2015 05:54 p.m. Para: topband Asunto: Topband: 160 QSO K1N On line log shows one but I was not on 160 for this event. I have no idea of date or time but if you are missing one and have a similar call, I might be the one. 73, Bob KI�G _ Topband Reflector Archives - http://www.contesting.com/_topband --- El software de antivirus Avast ha analizado este correo electrónico en busca de virus. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: HVDC
American Transmission Company built and activated a 345KW line right thru Madison, WI two years ago. Huge towers, huge green glass insulators. The line runs right past my XYL's office window, about 100' distance. Once activated, I used a Gauss meter to measure the magnetic field in her office - unmeasurable with the background AC fields from office wiring and computers. The highest readings were near light switches and a few old CRT monitors. Also, I drive right under the lines every day on the Beltline Highway in Madison, no effect on Madison Stations and I can even listen to the big AM radio stations in Chicago about 150 miles distant. I have much more power line noise along the secondary roads with lower voltage distribution 2.3KV to 68KV lines. You can read about it here: http://www.atc-projects.com/projects/rockdale-west-middleton-project/ select Rockdale-West Middleton So I'd recommend that you not pull up stakes. - - - BTW, the local utilities companies are converting their water, gas, and electric meters to RF remote read. The same people that fought the power line are now fighting the water, gas and electric utilities saying that their meters are bathing them in radiation that could cause cancer right in their own houses. Baloney! Also, the cellular telephone companies have been putting cell-site antennas on the light towers at local school sports stadiums - providing revenue to the schools. Due to an outcry by the same group people, the city has now outlawed cell phone towers on school property. More Baloney! I go to Radio Club meeting attended by many healthy 70, 80 and 90 year olds that have been sitting next to their rigs, amps and antennas since they were kids and are still healthy. So I'm not too worried and magnetic fields and RF. 73 Lloyd - N9LB On Tue, Feb 10, 2015 at 11:52 AM, Ws9v wrote: Hi All Through the center part of Illinois they have begun work at the government level to install a 690,000 VDC power line As with all this there is huge amount of opposition an even groups trying to ban it Does anyone have any experience with a line of such high VDC as a noise source ? It will pass within 3/4 of a mile south of my QTH I am really concerned my only hope if this goes thru is to pull up stakes an move rather than attempt to fight its noise Any thoughts de WS9V Skip _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Missing K1N 160m QSO records just uploaded to Clublog
All, They just uploaded the missing K1N 160m QSO records to Clublog site a few minutes ago. ~ 7000 entries! ... including my missing 160m QSO :-) 73 Lloyd - N9LB _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Looking for 160m narrow beam RX advice - an interesting combination of ideas
Thanks for the input. Yes, utilities are underground, located by the road - north side of property. This is adjacent to the proposed RX receiving area. I can detect no noise coming from these underground lines. South side of the property (adjacent to my backyard transmit towers) is idle farm land - no nearby noise sources. I can't put antennas on the farm property because of heavy snowmobile use in the winter. Residents of my rural subdivision must cross the farm to get to the extensive snowmobile trail system. -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Tom W8JI Sent: Tuesday, January 06, 2015 5:58 PM To: Lloyd Berg N9LB; topband@contesting.com Subject: Re: Topband: Looking for 160m narrow beam RX advice - aninteresting combination of ideas Finding a single RX antenna system that nulls the neighbor noise sources at 90 and 270 degrees is proving to be a challenge. If the noise sources are really at 90 and 270, and you have 30 feet or more for spacing at right angles to that, it should be fairly simple. Use a 180 degree out-of-phase array of two close spaced elements. If you want to make it directional in the main response, it would take two cells. You could just use two small loops in line with the nulls oriented at 90 and 270, and phase them for a unidirectional pattern. I could place a noise antenna next to each neighbor, mix the equal-length feed lines together ( in phase ) for the noise source null, and then place the actual receive antenna (in-line verticals, loops, K9AY or Shared Apex ) right in the very center of my yard ( centered/equidistant from the noise antennas ). It would not be that simple. You would have to match the levels, and have a proper main antenna. You could do that with a fader at the combiner and the correct main antenna, but it would be much more simple to build a directive antenna with deep nulls to the sides. Has anyone used multiple noise antennas feeding a single noise canceling device? I haven't. The odds of that working without independent phase shift and level control from each noise antenna is somewhat low, because it is unlikely the levels from sense antennas will independently have equal phase and level relationships to the main RX antenna you are trying to remove noise from. You are assuming the relationship of noise at common for sense antennas is the same phase and level relationship, allowing for some rotation that can be compensated out, as to the main. I don't think that is likely without some way to adjust each noise sense antenna independently. Far less complex would be using cells that null the sides where the noise is (easy since they are 180 degrees apart). If the individual cells do not hear the noise, they will not hear it when combined. Has anyone cascaded/combined a noise canceling device such as the NCC-1 or MFJ-1026 with a traditional short RX vertical(s) array or loop(s) or K9AY or Shared Apex? I have and I'm sure many others have, also. The problem is you have noise from two directions and two sources. The blessing is they are 180 degrees apart. If I were you, I would use a few small loops in an array. Real small loops with deep axis nulls, not loops that are configured to act as end fire verticals (K9AY, flag, pennant, etc), would null 180 apart very deep. This of course assumes the noise sources radiate from the directions you indicated. That might not be where they really radiate from, that just might be where the houses are. They might be radiating from multiple places spread over a large area, like back-feeding power lines with noise. Are the utilities underground? 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Looking for 160m narrow beam RX advice - an interesting combination of ideas
I have received many suggestions and ideas on this subject. Finding a single RX antenna system that nulls the neighbor noise sources at 90 and 270 degrees is proving to be a challenge. Greg has offered an interesting idea that would integrate noise canceling/nulling technology with a traditional RX receive antenna system. Possibly providing a best of both worlds solution. I want to share this idea with this group to see if others have any experience with this proposed solution. I could place a noise antenna next to each neighbor, mix the equal-length feed lines together ( in phase ) for the noise source null, and then place the actual receive antenna (in-line verticals, loops, K9AY or Shared Apex ) right in the very center of my yard ( centered/equidistant from the noise antennas ). Has anyone used multiple noise antennas feeding a single noise canceling device? Has anyone cascaded/combined a noise canceling device such as the NCC-1 or MFJ-1026 with a traditional short RX vertical(s) array or loop(s) or K9AY or Shared Apex? Thank you and 73 Lloyd - N9LB On Tue, Jan 6, 2015 at 10:55 AM, Greg Chartrand via Topband wrote: Looking for 160m narrow beam RX advice (Lloyd Berg - N9LB) I had a similar situation about 15 years ago with my next door neighbor who had something in his house that was giving me S9 raspy noise 24x7. I could not find the source in his house but I suspected his doorbell transformer that was buried inside a wall of his house. The noise precluded all DX on 160 not to mention everything else. I purchased an MFJ-1026 and had a sense antenna directly between my vertical (receiving antenna) and his house. I was able to completely null out the noise from his house right down to atmospherics. I worked a lot of DX using the 1026 and about 4 years later the noise went away without explanation. You can put up flags, loops, pennants... whatever but none of them will have a null anywhere near what you can do with a 1026 and sense antenna assuming that the noise source appears as a single point. You can verify this using a portable AM radio and using the loop-stick antenna in it to null the noise. If it nulls well, the 1026 would be a good investment. Good luck!Greg _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Looking for 160m narrow beam RX advice
I have read and re-read the recently posted 160m RX antenna information presented on the Top Band Reflector and am sold on building a separate low band receive antenna system in my front yard that is away from my TX towers in the back yard. I am wondering if anyone is willing to give me input on my situation. I need the best option for narrow beam RX. There are neighbor houses (noise sources) close to the property line on the east and west sides, and my house is on the south side, of the proposed receive antenna area. So I need both good front-to-back and good front-to-side rejection. The least visually intrusive antenna system for the front yard would seem to be something using short verticals or perhaps loops or flags hidden in the landscape plantings. Overall front yard dimensions are approx 130 x 130. Property line alignment is N-S. Desired receive directions would be NE-Europe, NW-Asia, SE-Africa, SW-VK/ZL. ( An aerial view of my QTH is available on Google Maps, satellite view ) Ground conductivity is poor, so I will need supplemental ground radials if I go with RX verticals. I cannot run ground radials onto my neighbors properties, so putting the RX verticals right on the property lines, with only half a ground radial system probably would not work properly. Recommended distances for a 160m four-square are either 135 feet which is not do-able here, or 80 feet which is do-able and would allow for 25 ground radials around all four RX verticals - but the side rejection looks to be minimal with an 80 foot array spacing. The other obvious options to a four square might be a pair of short verticals or flags or loops using an Antenna Phasing and Noise Canceling box such as the NCC-1. Any advice or hearing of your experience with a narrow beam RX system in a similar situation would be greatly appreciated. 73 Lloyd - N9LB _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: tool for install radials
One word of caution. Don't put the radials too far under the surface. 2, 3, 4, or 5 inches down is too deep! Remember that you will be cooking the soil ( introducing losses ) between the radial wires and the surface. Try to keep the radial wires an inch or less below the surface. 73 Lloyd - N9LB On Tue, Dec 9, 2014 at 7:45 AM, Jorge Diez - CX6VM wrote: Hello I think there´s a tool to make a line in the ground to put radials. Couldn´t find it in website, don´t know the name in English Could you please help me to find it or send me close up photos of yours to try to ask someone locally to make one? Thanks in advance 73, Jorge CX6VM/CW5W --- Este mensaje no contiene virus ni malware porque la protección de avast! Antivirus está activa. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: tool for install radials
Rob, I don't know you, but what I stated is absolutely true. I've been a broadcast engineer for 40 years, much of the time with a Potomac Field Intensity meter in one hand and a notebook in the other working on documenting AM broadcast antenna system performance and field signal strength. ( Also measured amateur systems on 160 and 80 meters when I could borrow the equipment. ) The losses from deeply buried radials is high and goes higher as the frequency increases. Yes the soil type and moisture content make a big difference, but close to the surface or on the surface is optimum. I know of what I speak. 73 Lloyd - N9LB SBE Professional Broadcast Engineer ( retired ) FCC 1st Phone ( a whole stack of them ) FCC General Radio License -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Rob Atkinson Sent: Tuesday, December 09, 2014 4:28 PM To: topband@contesting.com Subject: Re: Topband: tool for install radials One word of caution. Don't put the radials too far under the surface. 2, 3, 4, or 5 inches down is too deep! Remember that you will be cooking the soil ( introducing losses ) between the radial wires and the surface. Try to keep the radial wires an inch or less below the surface. That is absolutely not true. There is no difference in performance at any of those depths. 73 Rob K5UJ http://www.antennasbyn6lf.com/files/ground_skin_depth_and_wavelength.pdf _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Unknown Pulse Signal Wiping out 1900-1925 kHz
Pre-dawn here in Wisconsin, the noise is not detectable here as of 1245z Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Don Kirk Sent: Monday, December 08, 2014 6:12 AM To: Mike Waters Cc: topband Subject: Re: Topband: Unknown Pulse Signal Wiping out 1900-1925 kHz Hi Mike and gang, I have been monitoring the signal during the early hours of this morning and on web SDR in England it was there at 3am EST but when I checked again at 4:20am EST it was no longer being received. The heading from my house has been very consistent at approximately 75 degrees but somewhat difficult to determine exactly due to the pulsing nature of the signal. Signal still S9 at my location near Indianapolis at 7am EST. Signal is definitely at a heading greater than 45 degrees at my location based on numerous methods I have available, and estimated around 75 deg. As I type the signal just about dropped below my noise level at 7:04am (I thought it abruptly stopped but it is still there but right at my noise level at 7:10am EST I currently only have Internet via cellphone due to a large area outage on ATT DSL and when I get internet coverage back I will plot my heading to the signal to see what it shows. Don wd8dsb On Monday, December 8, 2014, Mike Waters mikew...@gmail.com wrote: From SW Missouri, heard on my 580' NE Beverage, pulses to S7 (preamp off), 1130 UTC (5:30 CST). I can hear it from 1.900 to 1.930 on the IC-765's 2.4 kHz LSB filter. Switching to AM on 1.915 (over S9), the signal has a rough pulsing tone, but I didn't try to measure the tone's frequency. @ 1145 UTC, pulses to S4-S6 Any educated guesses yet about its general geographical location? 73, Mike www.w0btu.com _ 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: Unknown Pulse Signal Wiping out 1900-1925 kHz
FYI 5-9 plus in southern Wisconsin Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of John Kaufmann Sent: Sunday, December 07, 2014 6:50 PM To: 'Topband' Subject: Re: Topband: Unknown Pulse Signal Wiping out 1900-1925 kHz It peaks at a heading of about 75 degrees from eastern MA, as best as I can determine on a Hi-Z 8 circle array. I made a video of its spectrum as captured on my Elecraft P3 and posted it on YouTube: https://www.youtube.com/watch?v=nwe0zp2XiuY. 73, John W1FV _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: EZNEC 5.0 +
The bad thing about high SWR in a high powered system are the resulting high voltage points and high current points generated by the forward and reflected waves. Those high voltages and current points can do a lot of damage to your equipment. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Charlie Cunningham Sent: Friday, December 05, 2014 6:30 PM To: 'Tom W8JI'; 'Charles Yahrling'; topband@contesting.com Subject: Re: Topband: EZNEC 5.0 + Well, I would respectfully disagree with Tom, that Return Loss is confusing or ,misleading. It's just another way of looking at reflections that often makes more sense of is more useful. For example, many filters etc. are specified in terms of their input return loss, usually in a 50 ohm system,and engineers working in the lab with vector network analyzers measure most all input matches in terms of return loss. On a Smith Chart, return-loss is a radially scaled parameter, as is VSWR. The origin of the chart, at a perfect match would be the 1:1 VSWR point,or the infinite return loss point. Conversely, the perimeter of the chart corresponds to 0 return loss or infinite VSWR. EZNEC and network analyzers tend to express things in terms of return-loss, although VSWR is also available. For modeling in EZNEC and tuning or sweeping your antenna models,you want to MAXIMIZE return loss and MINIMIZE VSWR- it's the same thing. As an example to illustrate Tom's point. IF we fed a resonant 1/2 Wave dipole at its center, with 600 ohm open-wire line, the VSWR on the feedline would approach 10:1, but there would be almost no loss in the feedline and virtually 100% of the incident power would be radiated by the antenna. The challenge would be to match the transmitter to whatever values of R+JX presented themselves at the sending end of the line. Have fun with EZNEC! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 05, 2014 4:40 PM To: Charles Yahrling; topband@contesting.com Subject: Re: Topband: EZNEC 5.0 + Return loss is just another misleading confusing way to express SWR. Return loss, like percentage reflected power, does not indicate any type of loss. It just expresses SWR in a different form. We can have 10:1 SWR, which would be a 1.743 dB return or mismatch loss or 67% reflected power, and still have virtually no loss. We can have 67% reflected power and still have nearly 100% of transmitter power getting into the antenna and being radiated. The best advice is to ignore it all, and just use SWR for now. :) - Original Message - From: Charles Yahrling cfytech2...@gmail.com To: topband@contesting.com Sent: Friday, December 05, 2014 3:29 PM Subject: Topband: EZNEC 5.0 + Just getting started modelling and looking for answers to questions not found in manual so far. For example, what exactly is included in the Return Loss figure shown in the SWR window? Just ground reflection loss, total system loss, something else? Trying to understand why Return Loss is greater for lower SWR curve values. e.g see this when toggling between std and alt impedance. What is this suggesting, go with lower return loss or lower swr curve? An incomplete grasp of the fundamentals is admittedly likely here g. 73, chuck -- de AB1VL NAQCC #6799 ab1vl.com _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4794 / Virus Database: 4235/8686 - Release Date: 12/05/14 _ 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: Broadband Inverted L
In my case, I started out with four radials, great wideband match ~100KHz When I had some more time and wire, I went to 8 radials, that cut the bandwidth in half, still a good match. Each chance I had to add more radials, I did. Each time the bandwidth decreased substantially, but the antenna kept working better with more radials as measured by my success working weaker and more distant stations. I'm up to 60 radials now, antenna is no longer wideband, but works better than ever. I figured out that I was cooking dirt back in the days that I had only a few radials. Now it requires a tuner to QSY more that 10 KHz, but again it works so much better. Examples, 160m worked and confirmed this year, W1AW in all 50 states, Amsterdam Is, Lord Howe Is, S. Cook Is. I suggest adding ground radials or a ground screen around the new feed point - as close to the surface as possible, and attach to the previous ground system too. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Joe Galicic Sent: Thursday, November 20, 2014 11:11 AM To: Mike Waters Cc: List, TopBand Subject: Re: Topband: Broadband Inverted L Mike, The antenna feed point terminates at a four foot ground rod and then I am running a number 14 wire from that ground rod to my existing radial field. That run is about 40 feet. The radial field consists of 3 8 foot ground rods and nearly 2000 feet of wire spread out over my entire front and back yard. I didn’t want to run new radials over top of the existing so that's why I did what I did. I am measuring SWR from the shack end of the feed line. My old L was only 35 foot vertical. I thought 65 foot vertical would be much better but sometimes the old L hears and transmits better by a couple S units depending on where the station is of course. So I think something is off? Hopefully I didn’t build myself an accidental dummy load? -Joe - Original Message - From: Mike Waters mikew...@gmail.com To: Joe Galicic gali...@comcast.net Cc: List, TopBand topband@contesting.com Sent: Thursday, November 20, 2014 11:17:16 AM Subject: Re: Topband: Broadband Inverted L It sure IS broadbanded. Couple of questions: On Thu, Nov 20, 2014 at 10:11 AM, Joe Galicic gali...@comcast.net wrote: The ground is connected to the existing ground system for the old L. Can you describe this? blockquote I get a 1.1 SWR reading from 1.8 to 1.9 before it moves up to 1.3 and slightly higher to 2.0. The antenna seems to be working OK (relative to the old L). This seems awfully broad banded? /blockquote Where are you measuring the SWR? At the feedpoint or at the end of the 125' coax? 73, Mike www.w0btu.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Help put Haiti on topband
I'm in Wisconsin and I've never worked Haiti on topband either. I believe there is a large stateside demand for HH on 160m. 73 Lloyd - N9LB On Tue, Oct 7, 2014 at 12:50 PM, Jim Brown wrote: On Tue,10/7/2014 8:36 AM, Carl Clawson wrote: there will be concentration on working Europe on the low bands How about working W6? In 8 years, I'm missing Haiti on Topband. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: BCB interference ?
Hi Ed! I've got a 1650 KHz 10 KW station about six miles away. I am using a Clifton Laboratories Z10022A high pass filter for 160 meter reception. Works great and very reasonable price. http://www.cliftonlaboratories.com/current_products.htm Z10022A Medium Wave High Pass Filter The Z10022A is a receive-only 9th order 1 dB Chebyshev high pass filter with a nominal cutoff frequency of 1800 KHz. The Z10022A is intended to be used to prevent a shortwave receiver from overloading due to strong signals from AM broadcast band (Medium Wave) in the 530-1700 KHz range. ( see the web site for lots of documentation). http://www.cliftonlaboratories.com/z10022a_high_pass_filter.htm 73 Lloyd - N9LB On Mon, Sep 22, 2014 at 8:50 AM, Ed Stallman wrote: Has anyone used this High Pass Filter ? http://www.dunestar.com/store/160-Meter-Highpass-Filter-pid-8.html I found I have a 25KW AM 1520 Khz BC transmitter 12 miles from me , is that close enough to interfere with me receiving weak signal DX on the top Band ? I do hear some wide band hash 1837 to 1840 ! Though I would asking before placing an order, not sure how what to look for with BCB interference ? Tnx Ed N5DG --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: BCB interference ?
Hi Ed! I've got a 1650 KHz 10 KW station about six miles away. I am using a Clifton Laboratories Z10022A high pass filter for 160 meter reception. Works great and very reasonable price. http://www.cliftonlaboratories.com/current_products.htm Z10022A Medium Wave High Pass Filter The Z10022A is a receive-only 9th order 1 dB Chebyshev high pass filter with a nominal cutoff frequency of 1800 KHz. The Z10022A is intended to be used to prevent a shortwave receiver from overloading due to strong signals from AM broadcast band (Medium Wave) in the 530-1700 KHz range. ( see the web site for lots of documentation). http://www.cliftonlaboratories.com/z10022a_high_pass_filter.htm 73 Lloyd - N9LB On Mon, Sep 22, 2014 at 8:50 AM, Ed Stallman wrote: Has anyone used this High Pass Filter ? http://www.dunestar.com/store/160-Meter-Highpass-Filter-pid-8.html I found I have a 25KW AM 1520 Khz BC transmitter 12 miles from me , is that close enough to interfere with me receiving weak signal DX on the top Band ? I do hear some wide band hash 1837 to 1840 ! Though I would asking before placing an order, not sure how what to look for with BCB interference ? Tnx Ed N5DG --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: W1AW/0
Any chance for some SSB for us mid-west stations? ( Yes, with amplifier ) On Mon, Jun 2, 2014 at 4:00 PM, n0...@juno.com wrote: FYI Topbanders...tonight is the last night to get W1AW/0 - Missouri on 160m until October. Freq about 1826, receiving up 1. 0200-0400Z or 9-11pm Central. There's a ton of static this time of year, so turn on those amps if you want to be heard! :D) 73, Charlie, N0TT _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Results OA4TT 3/8/2014
Hello Jack! Thanks for being QRV on 160m! Yes! Very much interest. Please activate your station on 160m again as soon as you can. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Jack Henry, OA4TT Sent: Saturday, March 08, 2014 10:52 AM To: topband@contesting.com Subject: Topband: Results OA4TT 3/8/2014 Hi Topbanders, We made 43 QSO's this morning EU-27 US-15 SA-1 To me conditions were not great. I had lots of problems receiving. Stations seemed to be hearing me much better than I was hearing them. This is still our summer and there appeared to be some storm activity over the Andes. I had to really dig on most stations to get the callsigns and as a result rate was low. Sorry to those I could not pull out. If there is interest we can try again in a month or so. QSO's will be on lotw in a few days. 73 Jack _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Ends for older Phillystran
To clarify, it was the original straight fiber version of Philly-strand that we had problems with at WDAE AM 1250 KHz. We were able to successfully compensate for the inner strand slippage characteristic by adopting a greatly lengthened foldback, large thimbles, and lots of clamps. If you do use the original straight strand version Philly-strand, just be aware of the slippage issue, adopt a more thorough system of clamping, and inspect it frequently! -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of James Wolf Sent: Tuesday, January 14, 2014 8:23 AM To: topband@contesting.com Subject: Re: Topband: Ends for older Phillystran On 01/13/2014 04:15 PM, Lloyd Berg - N9LB wrote: Hi Grant! I worked at WDAE Radio in Tampa, FL back in the 80's and 90's. The engineer before me decided to try the new technology Philly-strand guy lines on the AM directional towers because they had constant problems with the original segmented steel guy wires/egg insulators constantly arcing over whenever there was a thunderstorm in the area. To attach the Philly-strand, they used traditional metal saddle clamps on this early ( somewhat experimental ) Philly-strand installation. It was a real neat looking job with 3 clamps 3 inches apart and all within 8 inches of the ends of the Philly Strand. Just like you see on steel guy lines. It was written up in Broadcast Engineering Magazine with lots of pictures as the wave of the future for AM broadcast guyed towers. In reality, it didn't work well because we were constantly having to re-attach the lines because the inner strands pulled short inside the outer sheath, leaving just the outer sheath holding the tower up! ( nude towers, no antennas on top ).It didn't take long before we realized that we had to use a lot more foldback length and a lot more clamps! We went with 36 foldbacks with six clamps evenly spaced to keep things from pulling apart! That worked and stayed together for the remaining 10 years I worked there. Yes, we had to insert 6 feet of steel line at the anchor points to make up for the lost length at each end of each guy lines. No guarantees, but that was my experience with the original Philly-strand. If you decide to keep it, be very careful and inspect it frequently! They don't make that original Philly-strand for a good reason. 73 Lloyd - N9LB Lloyd, Was this the Phillistran that did not have the inner strands in a rope configuration or were they just straight fibers? Thanks, Jim - KR9U _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Ends for older Phillystran
Hi Grant! I worked at WDAE Radio in Tampa, FL back in the 80's and 90's. The engineer before me decided to try the new technology Philly-strand guy lines on the AM directional towers because they had constant problems with the original segmented steel guy wires/egg insulators constantly arcing over whenever there was a thunderstorm in the area. To attach the Philly-strand, they used traditional metal saddle clamps on this early ( somewhat experimental ) Philly-strand installation. It was a real neat looking job with 3 clamps 3 inches apart and all within 8 inches of the ends of the Philly Strand. Just like you see on steel guy lines. It was written up in Broadcast Engineering Magazine with lots of pictures as the wave of the future for AM broadcast guyed towers. In reality, it didn't work well because we were constantly having to re-attach the lines because the inner strands pulled short inside the outer sheath, leaving just the outer sheath holding the tower up! ( nude towers, no antennas on top ).It didn't take long before we realized that we had to use a lot more foldback length and a lot more clamps! We went with 36 foldbacks with six clamps evenly spaced to keep things from pulling apart! That worked and stayed together for the remaining 10 years I worked there. Yes, we had to insert 6 feet of steel line at the anchor points to make up for the lost length at each end of each guy lines. No guarantees, but that was my experience with the original Philly-strand. If you decide to keep it, be very careful and inspect it frequently! They don't make that original Philly-strand for a good reason. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Grant Saviers Sent: Monday, January 13, 2014 1:15 PM To: topband@contesting.com Subject: Topband: Ends for older Phillystran Hoping for some help to be able to use some older Philly. The factory tells me their grips won't work on parallel strand construction which is what I have, epoxy potted sockets are required. However, they only pot at the factory (liability etc etc) which means tossing 6 x 300' of 5/8 45klb ultimate strength. Newer Philly (post 1991) is constructed of 7 twisted strands, something like 7x19 wire rope (not exactly the same, but similar) and the PVC sheath transfers the load effectively with the Philly guy grips. Any reports of success with field potting, materials, how to do it, and where ends can be obtained (or a drawing, I will machine them) would be appreciated. I would have a load test done on each guy post potting. Grant KZ1W _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Ends for older Phillystran
Sorry, I meant to send this follow-up to the entire reflector. The newer version Philly-strand is excellent - it has become the standard for guying insulated AM broadcast towers, and is also used on some FM TV broadcast towers when guy lines have to pass thru the aperture of side-mount VHF and UHF antennas. 73 Lloyd - N9LB -Original Message- From: Lloyd Berg - N9LB [mailto:lloydb...@charter.net] Sent: Monday, January 13, 2014 5:15 PM To: Grant Saviers; topband@contesting.com Subject: RE: Topband: Ends for older Phillystran Hi Grant! I worked at WDAE Radio in Tampa, FL back in the 80's and 90's. The engineer before me decided to try the new technology Philly-strand guy lines on the AM directional towers because they had constant problems with the original segmented steel guy wires/egg insulators constantly arcing over whenever there was a thunderstorm in the area. To attach the Philly-strand, they used traditional metal saddle clamps on this early ( somewhat experimental ) Philly-strand installation. It was a real neat looking job with 3 clamps 3 inches apart and all within 8 inches of the ends of the Philly Strand. Just like you see on steel guy lines. It was written up in Broadcast Engineering Magazine with lots of pictures as the wave of the future for AM broadcast guyed towers. In reality, it didn't work well because we were constantly having to re-attach the lines because the inner strands pulled short inside the outer sheath, leaving just the outer sheath holding the tower up! ( nude towers, no antennas on top ).It didn't take long before we realized that we had to use a lot more foldback length and a lot more clamps! We went with 36 foldbacks with six clamps evenly spaced to keep things from pulling apart! That worked and stayed together for the remaining 10 years I worked there. Yes, we had to insert 6 feet of steel line at the anchor points to make up for the lost length at each end of each guy lines. No guarantees, but that was my experience with the original Philly-strand. If you decide to keep it, be very careful and inspect it frequently! They don't make that original Philly-strand for a good reason. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Grant Saviers Sent: Monday, January 13, 2014 1:15 PM To: topband@contesting.com Subject: Topband: Ends for older Phillystran Hoping for some help to be able to use some older Philly. The factory tells me their grips won't work on parallel strand construction which is what I have, epoxy potted sockets are required. However, they only pot at the factory (liability etc etc) which means tossing 6 x 300' of 5/8 45klb ultimate strength. Newer Philly (post 1991) is constructed of 7 twisted strands, something like 7x19 wire rope (not exactly the same, but similar) and the PVC sheath transfers the load effectively with the Philly guy grips. Any reports of success with field potting, materials, how to do it, and where ends can be obtained (or a drawing, I will machine them) would be appreciated. I would have a load test done on each guy post potting. Grant KZ1W _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: PT0S QSL Card
I received a very nice 2-part QSL card for PT0S about a month ago, used their Online QSL Request Service. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Phil Clements Sent: Tuesday, June 18, 2013 12:29 AM To: topband@contesting.com Subject: Topband: PT0S QSL Card I sent a $15 donation on November 30, 2012 via Pay Pal for my QSL card. I have had no communication at all, no card received! Is anyone else experiencing this, or did I just fall through the cracks? E-Mail to mgr. is being ignored. (((73))) Phil, K5PC All good topband ops know how to put up a beverage at night. _ Topband Reflector All good topband ops know how to put up a beverage at night. _ Topband Reflector
Re: Topband: Looking for OK, AK HI scheds for WAS
Hi Zack! I'm located in neighboring Wisconsin, running a FLEX-5000A, and a less-than-optimal 60 ft vertical. I found the secret to working HI and AK from the black hole of the Midwest. I've been able to work HI and AK many times when 160 really opens to those areas just before my local dawn. The enhanced band openings only last 15 minutes or so. When this occurs, the signals magically jump up out of the noise and working them with 100 watts while listening and transmitting with a short vertical is very do-able. The trick is to catch these short-lived enhanced propagation events. 73, GL, es HNY Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of vtnn...@comcast.net Sent: Monday, December 31, 2012 10:16 AM To: Topband List Subject: Topband: Looking for OK, AK HI scheds for WAS I am getting close to applying for my 160M WAS but have never been able to get OK, AK and HI. My marginal antenna (longwire of unknown length tuned remotely with a SGC tuner) does not help much for AK and HI and I am not surprised that I have never heard either location. If anyone is willing to set up a sched from OK that would be great. Would have to use some form of WSJT to make the AK and HI contacts. 73 Zack N8FNR ___ Stew Perry Topband Distance Challenge coming on December 29th. ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: Delta Loop vs Antenna Analyzer
Hi David! I have this problem with my hand held antenna analyzer too. I figured out that it was picking up AM and FM ( and maybe TV ) broadcast signals and those were interfering with the readings. I now use my LP-100A RF meter with about 5 watts of RF to get accurate readings. Yes, lugging a QRP radio and RF meter out to the antenna is not near as handy as a small hand held RF analyzer, but at least you get stable, reliable and repeatable results. http://www.eham.net/reviews/detail/5981, http://www.telepostinc.com/lp100.html 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of D Rodman MD Sent: Monday, December 03, 2012 10:22 PM To: topband@contesting.com Subject: Topband: Delta Loop vs Antenna Analyzer My 160m antenna died several weeks ago from a bad coax feed line and was restored just Sunday after the contest. I have tried several antenna analyzers and none seem to work with the loop antenna. I designed the antenna for 100 ohm feed and always wanted to put a half wavelength coax on an analyzer to measure R and J to achieve the best match. Calculated series transformer of 50 and 75 ohm coax seems to match the antenna quite well as anticipated. But, no matter how I try with any of my many devices, I can't get the boxes to work with the loop. The readings are not consistent. They just don't seem to like the antenna. Other wire or yagi antennas work as expected. Questions about if others have tried to measure loops or theoretical reasons why the various devices can't read the impedance are obvious and responses welcome. Thanks. David J Rodman, MD Assistant Clinical Professor Department of Ophthalmology SUNY/Buffalo Office 716-857-8654 ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: Spam:*******, PT0S
Same here, LOTW has not ingested any of my uploaded logs since it blew Up after the CQWW-SSB and CW-Sweeps. -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Herb Schoenbohm Sent: Friday, November 23, 2012 5:39 PM To: topband@contesting.com Subject: Re: Topband: Spam:***, PT0S Steve, I don't know what is going on with ARRL-LOTW as they have not uploaded a single file from me since November 5, 2012. All my contacts are OK with ClubLog and the PT0S site. Chris HA5X said all uploads have been going out but for some reason nothing appears on LOTW from any of my uploads. I sent them an e mail today and it appears everyone is gone for the holiday. So no joy here with LOTW at all! Do you know if others are experiencing the same problem? Herb, KV4FZ On 11/23/2012 6:29 PM, wb6r...@mac.com wrote: PT0S is QRT. OQRS is up and running. LOTW credits are already posted. Harry and Tomi are known for their low band DXpeditions and this one yielded another impressive low band total. Considering the great many obstacles, their success is a tribute to planning, resourcefulness and tenacity. We are all suffering from a lack of sleep. It is no longer just me, others are starting to fall asleep at the key. The entire crew is to be congratulated. If not a new DXCC overall, certainly most of us added a new mode or band. Now is the time to consider some extra support when requesting your QSLs. They don't require it, but they'll certainly appreciate it. http://pt0s.com/qsl.html 73 - Steve WB6RSE ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: 7O6T OQSL service
Hi Bob! I used the OQSL service a few days after they went QRT, haven't seen any cards yet. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Bob W4DR Sent: Saturday, November 03, 2012 3:26 PM To: topband@contesting.com Subject: Topband: 7O6T OQSL service Am I the only person who used the OQSL service for 7O6T and have not gotten a QSL. ? I know they must have gotten my contribution as I did get LOTW credit. Are they making more than one mailing for US cards? Bob W4DR ___ Topband reflector - topband@contesting.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.930 / Virus Database: 2441.1.1/5371 - Release Date: 11/03/12 02:44:00 ___ Topband reflector - topband@contesting.com
Re: Topband: 7O6T OQSL service
Hi Vladimir! Thanks for the information. Congratulations again on a great DXpedition. 73 Top band operators -Original Message- From: hamradio-spb [mailto:hamradio-...@yandex.ru] Sent: Saturday, November 03, 2012 4:12 PM To: Lloyd Berg - N9LB; topband@contesting.com Subject: Re: Topband: 7O6T OQSL service Dear friends! 7O6T cards were received from print 18 Oct. 2012 So steel need time to put lables on the card and little bit for sending ... Don't worry, wait please... 73! de RV1CC 04.11.2012, 01:06, Lloyd Berg - N9LB lloydb...@charter.net: Hi Bob! I used the OQSL service a few days after they went QRT, haven't seen any cards yet. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Bob W4DR Sent: Saturday, November 03, 2012 3:26 PM To: topband@contesting.com Subject: Topband: 7O6T OQSL service Am I the only person who used the OQSL service for 7O6T and have not gotten a QSL. ? I know they must have gotten my contribution as I did get LOTW credit. Are they making more than one mailing for US cards? Bob W4DR ___ Topband reflector - topband@contesting.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.930 / Virus Database: 2441.1.1/5371 - Release Date: 11/03/12 02:44:00 ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: Antenna analysers in close proximity to BC station.
I have the same problem with a 50KW FM station a couple of miles away affecting my Palstar ZM-30. It is useable on the rig side of an antenna tuning unit, but most of my antennas are self resonate therefore the FM broadcast RF rides right into the bridge making it mostly worthless when directly attached to any antenna such as a dipole, vertical, yagi, etc. Sometimes I can get a useable reading if I turn the antenna 90 to the broadcast tower, but that only works with the rotatable antennas. Experiments with filtering using small value caps, small pi networks, a series FM trap, or ferrites have been unsuccessful. Any filter I put in front of the analyzer influences the reading substantially. BTW... this broadcast station also comes in on my frequency counter too, with no antenna attached. Please let the group know if any of you have come up with a transparent at ham frequencies inline filter. 73 Lloyd - N9LB -Original Message- From: Topband [mailto:topband-boun...@contesting.com]On Behalf Of Tom Boucher Sent: Friday, November 02, 2012 4:21 PM To: 160 reflector Subject: Topband: Antenna analysers in close proximity to BC station. A ham friend asked me to design a matching network for his 160 metre end fed quarter wave, so I asked him to provide an impedance reading using his MFJ-259B. I would then use the Berkley site (http://bwrc.eecs.berkeley.edu/Research/RF/projects/60GHz/matching/ImpMatch. html ) to provide the necessary values for an 'L' network, as I have done many times at my own station. The readings he provided were total nonsense and quite erratic, so we concluded his MFJ-259B was dead. He assured me that he always does a static discharge before connecting the MFJ. So I paid him a visit, taking along my Palstar Antenna analyser thing, which has always performed well at home, and what-do-you-know, the readings on that were also erratic, total nonsense and it behaved in a way I have never seen before. Than someone suggested the problem may be due to a 50Kw BC station on 909 KHz, situated less than 5 miles away, causing both antenna analysers to misbehave. We ended up with a good old-fashioned link coupled parallel tuned circuit with the antenna tapped a few turns up from the ground end. This works fine but he is power limited due to arcing across the tuning capacitor. So we would ideally like to revert to the 'L' network plan, but how to use the antenna analyser in the presence of a high BC station field. Anyone any ideas? 73 Tom G3OLB ___ Topband reflector - topband@contesting.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.930 / Virus Database: 2441.1.1/5369 - Release Date: 11/02/12 02:34:00 ___ Topband reflector - topband@contesting.com
Re: Topband: Best angle of radiation ?
I was involved in broadcast engineering for many years ( probably one of the reasons for my interest in 160m and AM ). There were numerous technical write ups about stations who wanted the maximum theoretical ground wave signal and spent big bucks to put up 5/8 wave verticals. They were always disappointed in the unexpectedly reduced coverage area that resulted. Most of the reasoning for this unexpected negative result was attributed to the minor high-angle lobe produced by the 5/8 wave coming back down and interfering with the main lower angle signal. As a result, those station who had experimented with 5/8 wave towers usually reduced them to 1/2 wave or less. 73 Lloyd - N9LB ___ Topband reflector - topband@contesting.com
Re: Topband: radial wire source
Hi Dan! I use #12 solid solid copper THHN house wire - around here Menards has the best price, HD has gotten very expensive in the last year. I strip the insulation off with a little jig I made utilizing an imbedded utility knife blade. I like the direct copper to soil DC contact rather than laying insulated wire on/in the ground. Also the solid bare copper wire won't leach away into the soil for 40-50 years. Never bury bare stranded wire because it disintegrates way too fast, which is why the National Electrical Code requires that all ground wire be solid. 73 Lloyd - N9LB On Tue, Jun 5, 2012 at 8:01 AM, Dan Bookwalter wrote: I think I asked something similar last fall , but , circumstances changed and I couldn't do anything about it at the time... So , here I am again looking for a source of radial wire I was thinking of either going with K2AV's FCP or a radial field If i go with the radials I was thinking of using #14 stranded for about 15 radials that in theory would help absorb any lightning impulses (per W8JI website) , then I was going to use whatever wire I can find for the remaining 40 or 50 radials. My radial field can only cover from about SW thru North over to East. Is there a better source for wire than Lowes/Home Depot ? I will check with the local electrical distibutor , but , if I recall correctly they weren't much better Lowes currently has 500' of #14 THHN for $50 I would need about 3000 feet. Dan ___ UR RST IS ... ... ..9 QSB QSB - hw? BK ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: 2011 ARRL 160 Contest Results - N9LB
N9LB 2011 ARRL 160 Contest SOLP 100 watts, 60 ft vertical, 60 radials. This is the first year that I've operated in the ARRL 160 contest. By the time I got home on Friday and had something to eat, and got into the shack it was 0113z. First station worked was K7KU in WY. After that, mostly eastern states until around 11 PM ( 0500z ), then worked a series of western states and three DX stations, but fell asleep around 3:20 AM ( 0920z ) ( I just can't stay up all night like I once could ). Picked it up again late Saturday afternoon ( 2245z ) until 1:35 AM Sunday, fell asleep again. Picked up afew more Sunday morning between 1300 and 1400. 272 QSOs: Penn: 24 stations(e+w) Minn: 21 stations Virg: 17 stations Ill: 15 stations Ohio: 12 stations Tenn: 11 stations Wisc: 9 stations States missed: WA, OR, MT, ND, AK, HI Canada, worked: SK, BC, ON, QC, MAR DX, worked: PJ2, VP2, ZF2. ( heard east coast stations working Europe, but I couldn't hear them here. ) Next year I'm going to try to take Friday off, try to take a nap Friday afternoon, and be on the radio right from the beginning. Also hope to have a K9AY receiving antenna set up and working by then. See you all in the Stew Perry and CQ-160s. 73 Lloyd - N9LB ( EN52 - Wisconsin ) ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Using a DX-Engineering 80m vertical as part of an inverted L
Hi Ken! I had a 42 vertical tuned for 160, worked awful! A random long wire run from my first floor window to near the tower top then onto / into a ~30 foot tree and back to the peak of the root at the far end of the house. That random wire worked much better than the 42 vertical on 160. I have now replaced the 42 foot vertical with a 65 foot vertical - the 65 footer works much much better on 160! I also use it for 80/75, 60 and 40 meter use. ( the performance on the 80/75, 60 and 40 m bands is nearly identical between the 65 and previous 42 footer. ) Your mileage may vary. 73 Lloyd - N9LB -- Message: 1 Date: Tue, 1 Nov 2011 10:20:58 -0400 From: WA8JXM wa8...@gmail.com Subject: Topband: Using a DX-Engineering 80m vertical as part of an invertedL on 160? To: TOPBAND TOPBAND@CONTESTING.COM Message-ID: 9fd8c661-76f5-4a34-8da5-91ea0b4c2...@gmail.com Content-Type: text/plain; charset=us-ascii I am wondering if anyone has used a DX-Engineering 80m vertical as the vertical part and the support for a 160m inverted L, connecting the rest of the required length to the top. Of course there would have to be one or two guys to counteract the pull of the horizontal part of the L.Seems like a reasonable way of getting a 65' vertical support. On a related note, how much real difference would a 65' vertical section make vs a 40' one (total radiator length being the same?) Although an eighth wave vertical portion seems like it would be worthwhile, I have to wonder if in the real world it would make a significant difference vs. a 40' vertical section. Tnx, Ken WA8JXM -- ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: Fabricated common mode chokes - Sourcing
Hi Tod! Thanks for the data. I'd like to build up several toroid chokes for 160, 80 and 40 meter use. I looked at the Fair-Rite site, no 31 material. I looked at their vendors and went to Amidon ...amidoncorp.com/items/19 Amidon does have F Material Ferrite Toroids High Saturation flux density at high temperature. For power conversion transfomers. Good noise suppression from 0.5 to 20 MHz. They offer an F material core: FT-240-FC ( $20.00 ea ) Inner Diameter 1.4 Outer Diameter 2.4 Height 0.5 Al Value 4107 Is this material suitable or am I barking up the wrong tree? 73 Lloyd - N9LB Begin forwarded message Subject: Topband Digest, Vol 104, Issue 21 Date: 8/29/11 2:00:40 PM From: topband-requ...@contesting.com To: topband@contesting.com 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. Fabricated common mode chokes and their impedances (Tod) -- Message: 1 Date: Sun, 28 Aug 2011 16:51:14 -0600 From: Tod t...@k0to.us Subject: Topband: Fabricated common mode chokes and their impedances To: topband@contesting.com, towert...@contesting.com Message-ID: 0E6261DE04D24FDDA95DBC885D2CE12F@g2 Content-Type: text/plain; charset=us-ascii This probably has a limited audience but I do know that there are some readers on this list interested in fabrication of high impedance common mode chokes for their stations. I built and measured 18 of this type of choke during the past week. There is a write-up on my web site which shows how they were fabricated, how they were measured and the measurement results. I used Fair-Rite 2.4 inch diameter type 31 toroidal cores and small diameter [RG 59 size} coax. I measured the magnitude of the impedance for each of the chokes on the 160, 80, 40, 20, 15 and 10 meter bands. There are also attenuation values for each choke [specific to the 50 ohm measurement circuit]. The results are shown as a series of graphs for two cores, three cores and four cores with 3, 4, 5, 6, 7 and 8 turns on the core bundle. These graphs should provide guidance to those fabricating their own common mode chokes. The site is http://www.k0to.us/HAM/ham.htm The article is under Experiments Measurements Measurement of Chokes made using type 31 material cores My work is an extension of material found in the excellent paper on this subject written by Jim Brown, K9YC, which has been mentioned here before. Tod Olson, K0TO -- ___ Topband mailing list Topband@contesting.com http://lists.contesting.com/mailman/listinfo/topband End of Topband Digest, Vol 104, Issue 21 ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
