Re: Topband: 160 vertical/L
On Wed, 2016-11-30 at 15:22 +0100, Maciej Wieczorek wrote: > Hi , > > did anyone try to match such 160m vertical /L or /T on 80m? > How about efficiency? > > After my 31m tall vertical broke last sunday (now it's 23m only) my > idea is > to add 2 x15m top loading wires, making a T-vertical. 160m is a > priority in > this case and I know it will work OK, but I'd like to use it also on > 80m. The easiest thing to do might be to add a second wire for 80m. Lifting a (fiberglass?) spreader to keep that second wire at a distance should not add all that much weight. -- All Rights Reversed. _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New digital mode?
On Mon, 2016-10-03 at 15:06 -0500, K4SAV wrote: > I asked this question on QRZ and never got a good answer. I am sure > many on this reflector know the answer to this question. > > What is the stuff on 1838 kHz that sounds like a continuous carrier > with > no modulation. Looking at it on the band scope I can see some > modulation > (I think) but it is very small and it is not discernible by ear. The > signal has a regular transmission length (maybe 1 minute, I didn't > time > it). I know what PSK31 and JT65 sounds like but that is not what I > am > hearing. You are hearing JT9. The WSJTX software can decode both JT65 and JT9 at the same time, if you select JT9+JT65 as the mode. 73 de AB1KW -- All rights reversed _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Modeling the proverbial vertical on a beach
On 08/13/2014 09:47 AM, Tom W8JI wrote: Transmitting is a different story, if lower angles are used. I doubt, however, it is ever close to 10-20 dB unless it is groundwave propagation. I'm sure people somewhere have actual numbers on that. One big question is, where does the path loss on top band come from? Is the path loss due to energy lost with each hop? If so, bending some of the radiation around the earth a little bit, and reducing the number of hops that way, could be a significant factor. On the other hand, going through the D layer at a shallower angle could also mean more signal absorption at certain times of the day. This may explain the I got more signal on my horizontal dipole right around sunrise/sunset than I got on my vertical anecdotes. IIRC, this difference has been reported to be 1-2 S points by some people. A similar difference (1-2 S points) when going the other direction (lower angle, over a low loss medium) seems reasonable. 20dB does seem a little out of place, unless the losses incurred with each ionospheric hop are larger than I suspect :) _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: duo-band 80m/160m antenna
On 06/03/2014 11:15 AM, Carl wrote: What about two seperate antennas with a common feed? Have the 80 as a vertical and the 160 spaced from it a foot or so and then go to a L or T at the top? The double L antenna is just that: http://www.yccc.org/Articles/double_l.htm I do not know how it stacks up against an antenna with a large(?) number of elevated radials, but it sure is simple to build and seems to radiate fine. _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Ladder line vs coax loss epiphany
On 04/30/2014 11:08 AM, Shoppa, Tim wrote: I briefly used the window line you all are discussing, before I built my own parallel line from scratch. It is surprisingly easy to make one's own ladder line, on a budget, from materials that are locally available. I have made ladder line from 12ga THHN wire, 1/4 tubing, UV resistant zip ties, and super glue. First, I cut the 1/4 inch tubing in many pieces of equal length, representing the distance between the wires. Then, I string up two lines of copper wire near each other, at a convenient to work with height. This can be done between two trees, between a tree and the deck, etc... To assemble the ladder line, I run a zip tie through the tubing, around one wire, back through the tubing, around the second wire, and then I ratchet it close. I put spacers on about every foot and a half. Afterwards, I run by and snip off the zip tie ends, followed by another run to put a drop of superglue where each zip tie touches the wire. Ladder line like this has been up both at my house, and at a friend's place, for a few years now. It is a lot easier to make it this way, than to run hundreds of feet of copper wire through ready-bought spreaders. I did take pictures at one point. If someone wants the illustrated version of the above description, I'll type up a blog post with pictures. If someone has ideas on how to do it better, I am all ears :) _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: ARRL Board Requests Member Comments About Digital Modes
On 03/03/2014 06:37 PM, Joe Subich, W4TV wrote: What is really a concern is the demands by wideband data advocates for priority access to *at least 15%* of every amateur band in spectrum coordinated in all three ITU regions. See: http://hflink.com/bandplans/iaru_region_2.html Applied to 160 meters, that would wipe out 1810 to 1840. On 80 meters Apparently you did not read that URL. They're not even asking for 1810 to 1840. that would wipe out the entire CW/RTTY band from the top of the extra CW allocation, on 40 meters again it would monopolize the band from the top of the Extra CW allocation to well into the foreign phone band. On 20, 17, 15, and 12 it would wipe out the entire spectrum currently used for RTTY/PSK/JT plus most of the non-extra class CW area and on 10 it would use up the entire CW/data band well into the beacon band. Even though the comment period is officially over on RM-11708, it is far more important to continue to tell the FCC No on 11708 than worry what ARRL may suggest in terms of an unenforceable band plan. Equating RM-11708 with something the proposed band plan from the URL above DOES NOT EVEN ASK FOR, and giving that as a reason to oppose RM-11708 is nothing short of disingenious. Never mind that the proposed band plan is a totally separate thing from RM-11708, and it would be totally legitimate to put the automatic digi stations in the parts of 160, 80 40 that are region 2 only, keeping the automatic stations totally out of the way of DX. The hflink band plan may be in need of improvement before it can be considered, but that does not seem like a valid reason to oppose RM-11708... -- All rights reversed. _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160M Rhombics
On 07/26/2013 04:23 PM, ZR wrote: For the guy who has the land and wants to own 20-10M in one or two directions for his daily chats, a rhombic will cost a lot less than a rotating tower with stacked yagis for each band. Also consider what seems like a very narrow beamwidth at the antenna can cover a lot of the planet by the time it reaches its antipode. With 2 rhombics and some relays to switch termination points a mighty potent signal can cover a lot in 4 directions. You can do the same thing even cheaper, and probably with slightly higher gain, with two lazy H antennas for 20-10m :) I have one lazy H pointed east west, and am itching to build one that points north south, once the leaves fall off the trees... -- All rights reversed. _ Topband Reflector
Re: Topband: [ARRL-LOTW] BoD votes LoTW initiatives
On 07/23/2013 10:46 PM, Joe Subich, W4TV wrote: §97.307(f) Âno longer reflect the state of the art of digital telecommunications technology, and that the proposed rule change would Âencourage both flexibility and efficiency in the employment of digital emissions by amateur stations. The Ad Hoc Symbol Rate Rule Modernization Committee was dissolved with the thanks of the Board. That part is definitely true. Various low symbol rate Olivia, Contestia, MFSK and DominoEX modes (which are legal) take up more bandwidth than psk500 (which is currently illegal). Save us from a Board of Directors that would not know Digital Operation if it bit them on the ass. All we need is a bunch of 2.8 KHz wide chunks of white noise across the entire non-voice spectrum. If they want to remove the symbol rate, the bandwidth better be compatible with that of CW (100 Hz or less) in the majority of the shared non-voice spectrum. Seggregation by bandwidth might make sense, but I am not sure that needs to be written into FCC rules. A band plan may be a more appropriate way to deal with that, especially considering the fact that different countries have slightly different ham frequencies and rules... -- All rights reversed. _ Topband Reflector
Re: Topband: RIG PROTECTION FROM BEVERAGES
On 01/16/2013 10:22 AM, Wayne Willenberg wrote: I have been looking on the Internet, and one possible solution is Array Solutions Model AS-RXFEP, RF Front End Protector. The advertising claims to protect in the feedback situation as well as in a lightning situation. The insertion loss is claimed to be only 0.3dB. For only $55 this seems like a good investment. Does anyone have experience with this unit or would you please suggest an alternative? You can build a near-equivalent to this yourself. You want two series of 4 or 5 schottky diodes between the signal and ground, in opposite sign to each other. This limits the maximum voltage across the radio's signal input to 2V or so. Secondly, you want to limit how much current flows through the diodes, so they are protected. You can do that by having a 5 to 10 ohm resistor in series with your signal, between the beverage antenna and the point where you have the diodes to clip the signal. That will limit the current to a small enough amount that the diodes should not get damaged, and the voltage should not go up just because there is a higher current flowing through the diodes. If you want to protect this circuit from higher potential discharges (eg. nearby lightning strikes), you can always put a TV coax gas discharge tube protection device between your the antenna and diodes+resistor circuit. Another solution is to have a relay that switches your beverage in and out, based on one of the signals put out by your radio when it receives (or transmits). Chances are the amplifier or transverter control port on your radio will have a suitable signal. _ Topband Reflector
Re: Topband: Monopole Elev Pattern w.r.t. Earth Conductivity
On 10/24/2012 06:37 PM, Mike Waters wrote: So according to your tests, the ~5/8 wave tower was always inferior to the 190' tower, no matter what the distance was? That is very interesting, And I have little doubt all your towers had sufficient radials under them. :-) What do you think about 120' vs 190' ? Ever do any tests like that? I wonder if it would be an idea to try these ideas on 40m. That way it could be tested with much antennas small enough multiple people might be willing to set them up for testing. ___ Topband reflector - topband@contesting.com
Re: Topband: electrical wavelength
On 09/10/2012 07:42 PM, DAVID CUTHBERT wrote: Run the numbers and for RG-6 we see that sq root of L/C is good above a couple hundred kHz. Does that have any consequences when planning phasing lines for a receive 4-square that is to be used on eg. 137 kHz? Are there types of coax that are more predictable on LF? Would the quad-shield RG-6 be better, due to having more shielding (and more shield than skin depth)? -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Monopole Radiation Patterns, takeoff angles etc
On 05/06/2012 11:10 AM, Richard Fry wrote: Unless that propagation path is obstructed by some physical object, nothing prevents such low-angle waves from traveling on to the ionosphere, which under the right conditions will result in their reflections returning to the earth as skywave. The problem is that radiation does not just have an amplitude, it also has a phase angle. At certain ground resistances, the ground wave and the low angle sky wave will cancel each other out, which moves the angle of radiation up. None of this is anything you really have to worry about. Top band is a lot like camping: you do not need to outrun the bear, you only have to outrun the other campers. If you can get vaguely reasonable gain at 10-20 degrees takeoff angle, you have outrun the other campers. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: It is not so much propagation
On 03/19/2012 06:46 PM, ZR wrote: A 175' run of 5 Slinkys will have about the same directivity as a 550' or so Beverage, a bit better SNR and still enough signal to not need a preamp most of the time. Its still a Beverage. Statement based upon years of use. YMMV A beverage works because the difference in velocity factors (between air and wire? between wire and ground?) bends the wavefront. Does a slinky, with a lower velocity factor, bend the wavefront more? Does it somehow end up with a lower takeoff angle, and maybe better azimuthal directivity than a similar length of straight wire? I am somewhat checked out from work right now, or I would model this in NEC. Right now I'm hoping someone else already has :) Also, do you need special slinkies for constructing a beverage? Say, stainless steel or bronze ones? -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: LOTW Participation
On 02/17/2012 09:16 AM, Eddy Swynar wrote: Great! But what if the ARRL, and others, was to suddenly announce that they'd no longer issue hard copy certificates---virtual awards only, viewable on-line...? I wonder if that might cool one's enthusiasm for ANY paper-chasing. We now have virtual QSL cards---can virtual awards be far behind...? Selling the physical awards, which many people want to have, appears to be one of the main things paying for the cost of running LOTW. As long as LOTW will have bills to pay, I imagine the ARRL will continue selling physical awards. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Radials help
On 02/12/2012 10:15 AM, Guy Olinger K2AV wrote: And you will be hearing 160 4 squares built with FCP's, taking up less space than one conventional 1/4 wave vertical with 1/4 wave radials, eliminating the issue of what to do with crossing radials. I plan to do a similar thing on 80m, though probably with double L antennas (vertical dipoles with the ends running horizontally). An array of 3 or 4 of those looks like it can outperform a single vertical with a good ground system (which I do not have space for), and give some directivity, for better reception. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Radials help
On 02/11/2012 01:12 PM, k2...@juno.com wrote: Hi Jack, Are you saying that the FCP works just as well as an elevated or buried radial field??? I was under the impression that the FCP was just a way to get on 160 when there wasn't room for a radial field... The FCP, and also the double L antenna, work as well as the (poor) radial systems that many people can put up. It will not outperform a proper radial field with many dozens of quarter wave radials. According to NEC (which I know is not very accurate), both the vertical with FCP or a double L antenna are about 6dB below the output of a vertical over perfect ground - which a vertical with 120 quarter wave radials gets fairly close to. If you cannot fit a large radial field in your yard, and would be making do with a small one anyway, it may be worthwhile to just lift the whole antenna off the ground. This may lose you 1-3 dB over a good vertical with a smaller radial field, with the benefit of coming relatively close without having to dig up your yard. If you have the space and care about your signal strength, you'll probably be better off with a full radial field. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: What do you use as a RUN Antenna?
On 01/31/2012 07:30 PM, D Michael wrote: I tried using my TX TEE but my neighbor now has a plasma TV and all I hear is that thing. How can they pass emmission testing and be legal? It looks like Part 15 has separate rules for emissions conducted back onto the power line (15.107) and emissions radiated into the environment (15.108). The radiated emissions limit section does not appear to specify any radiation limits below 30 MHz for unintentional radiators... http://www.access.gpo.gov/nara/cfr/waisidx_06/47cfr15_06.html Am I missing something, or did part 15 change? -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Unintentional QRM on TB
On 01/25/2012 03:56 PM, W0UCE wrote: There is unintentional QRM on all bands when DX is working Split. People don't check to make sure they are using SPLIT and TX on the DX stations calling freq. I know this for fact as I have been unintentionally guilty myself for not looking to make sure... Even worse is forgetting to clear split mode after working the DX. Then you end up spamming the frequency where the DX is listening, while trying to make your next QSO... I seem to do this every once in a while :( -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Ticked over intentional interference on top band
On 01/21/2012 12:28 AM, Greg wrote: answered...the dx station says QRZ AD and you hear something like GH, BGN, or RJ and many others calling, calling, calling not because they can't hear...because they are too self-centered and inconsiderate to wait and let AD make his QSO and finish. It's disgusting behavior. What can we do? I have actually heard a dxpedition put some particularly badly behaving ham on their own little blacklist, telling him off on the air and promising to never put him in their log because of bad behaviour. After that, the badly behaving station disappeared, and several other stations mysteriously started behaving... -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: 160M JT65HF
On 12/30/2011 04:14 PM, Jim Brown wrote: On 12/30/2011 9:14 AM, Joe Subich, W4TV wrote: Most JT65 activity is relatively low power - typically between 10 and 50 watts on HF. Yes, but if I were trying to work a difficult path like EU on 160M from here in W6, I would be running as much power as I thought my power amp could safely handle for the 50 second keydown cycle -- (probably about 500W). Thor's very informative post about the far more limited spectrum on 160M in his country was also quite helpful, and it helped a lot in understanding his concerns. Agreed. I believe it would be a polite thing for all the digital ops to happen around 1838, so as to not cause interference to the CW ops lower in the band. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Digital on 160m?
On 12/29/2011 11:22 AM, Ian Wade G3NRW wrote: This winter I plan to try various digital modes on 160m (JT65, WSPR, V4, PSKxx etc), but I have no idea where to transmit. Are there any established frequencies or frequency ranges on Top Band where these modes congregate? Unfortunately, there seem to be two. 1807 and 1838 are where I have seen most digital transmissions on 160m. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: BCI
On 12/13/2011 05:36 PM, Scott Long wrote: A strange happening already this season, I am hearing WTVN-AM 610 khz (Columbus OH) plain as day on 1830 khz. This is the only frequency that I hear it on. I am at least 35 miles from this station, and it is west of me. Wouldn't be the first time an MW station puts out a signal on a harmonic frequency. This happens all the time. If you tune around between 2 and 3 MHz, you will often find a handful of broadcast harmonics. Some come and go, others are more permanent (like 2730 kHz). The way to get them fixed is to notify the station and get them to fix the problem. If they don't, notify the FCC... -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: no response to query: feeding phased verticals at half wave spacing
On 11/22/2011 08:06 PM, Gerry Treas, K8GT wrote: Hi Dale, I'm no antenna expert, but certainly read as much of the experts publications as I can get my hands on, but having a Teflon brain, it doesn't stick very well. That said, the ARRL Antenna Book has a page that shows the patterns of various spacings and phasings of vertical antennas, which I found very enlightening. Enlightening, but also somewhat misleading... The patterns in the ARRL Antenna Book are correct if the current in both elements is the same. However, if you feed an array of antennas with delay lines, those delay lines will act as impedance transformers for the antenna impedance of each element (like all feedlines do). This can result in each element getting different currents, and the pattern no longer being what it was. This makes feeding a phased array with delay lines much trickier than one would imagine at first glance. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Receive ant question
On 10/26/2011 09:27 AM, Mark Beckwith wrote: I think a front end protector is some good amount of insurance. I listen on other receivers while transmitting. I have cooked an IC746PRO doing this and it was quite annoying. It tricked me into thinking everything was fine because it worked okay for a good long while, but ultimately I cooked it and felt like an idiot. With the RX antenna a reasonable distance (100ft) away from the TX antenna, would an RF limiter (like the one ICE makes) be an acceptable substitute for a front end protector with relays? I am running 100W only here, no amp. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Effect of current max not at base of vertical.
On 09/17/2011 01:19 PM, Richard (Rick) Karlquist wrote: I'm still waiting to see an actual measurement showing that a 1/2 wave vertical with minimal radials is worse than a 1/4 wave vertical with radials. My measurements were over high conductivity ground. Maybe they would be different in the desert. That's hard to imagine. A 1/2 wave vertical without any radials at all is only a few dB (2-6 depending on ground type and exact antenna shape) below that of a 1/4 wave vertical over totally perfect ground. I'm sure a 1/4 wave vertical with 8 raised radials, all raised maybe 10-20ft above ground, would be better still - but only by a few dB and it'd take up a lot more real estate... -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Newbie Antenna Question (long)
On 09/05/2011 11:03 PM, Jim Bennett wrote: I accept the fact that a vertical antenna is the best bet (for transmitting, anyway) 160 meters, AND that the Inverted L is basically a vertical antenna. If that is the case, does this mean that it radiates just like any other vertical, primarily omnidirectional? If it is omnidirectional, does it matter in which direction the horizontal portion of an Inverted L is aimed? I can run mine in either of two different directions; one higher, but not too stealthy, the other direction a tad lower, but more hidden from the HOA Nazis. Oh, and yes, I am planning on installing several long radials. It would be great if I could plop down 50-100 of 'em, but that isn't realistic, either! I've already got two strung out along the fence perimeter, and I might be able to get one or two more put down, providing the XYL doesn't go ballistic with all the wire strung out around the house. At least she's also a ham, so she might cut me some slack on that part of the project! The double L antenna could be a stealthy alternative too, which does not require radials. It outperforms an inverted L with a smaller number of radials and comes pretty close to the performance of an inverted L with a reasonable number of radials. Depending on how much copper you want to sink into the ground (60+ radials could be a lot of work and I don't know how much time/energy you have), it could go either way. Here is some info on the double L antenna: http://www.yccc.org/Articles/double_l.htm http://surriel.com/radio/160-meter-double-l-antenna As you can see from the photos, it's barely visible. The performance is 6dB (1 S point) below a vertical over perfect ground. That corresponds to maybe 2-3dB below that of an inverted L with 30-70 1/4 wave radials over poor ground. Given that I do not have the space for that many 1/4 wave radials on 160m, I'll take the low effort antenna any day over 2dB more performance for 10x as much work :) You can add radials over time to get some more performance, but the double L does not require them to get started... -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: why radials? K8UR or 4SQ array
On 08/26/2011 07:44 PM, Jorge Diez - CX6VM wrote: this K8UR system don´t need radials!, and have more gain than the traditional 4 square, so my question is why I will spend $ to upgrade from K8UR system to a 4 square if it have less gain? Don't. A 4 square array is very useful for people without 200 foot antennas, and with space for radials. If you have exceedingly poor soil and more vertical space than radial space, an array of vertical dipoles may simply make more sense for your installation. I plan to build two arrays of vertical dipoles too, suspended from my trees. These will be for 40m and 80m, with the ends of each dipole folded over a little, double L style. This beats verticals in my qth, since I don't have quite enough space for radials and the soil is very poor. Lifting the point of maximum current off the ground is simply the better option for my yard. It sounds like the same is true for you. -- All rights reversed. ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
