Topband: PE coated RG6
I would like to thank everyone who replied to my question both in PMs and in the respective forums. As many of you know, I have been making cables for years professionally but this one, like connectorizing RG174, stumped me. The issue is getting compression F connectors on the PE coated RG6 I am using to feed my K7TJR four square receive array. I have never had a problem putting F connectors on my PVC coated RG6. The problem is getting the PE to expand enough to accept the ground innards of the F connector and properly seat the center conductor of the coax with the foam at the end of the opening. I have tried heating the PE and that works, kinda. Doing it in the field far from the house, on a cold winters day, means you have to judiciously use a torch to warm the PE. One suggestion was to use hot water. I will give that a try later today. The suggestion that has worked on three test connections came from Joel at the RFC, another cable manufacturer. He suggested doing the standard cable prep as you would do for PVC. He then suggested two ½ lateral cuts in to the PE at the 12 and 6 positions and then push the connector on to the cable. Eureka! Joel also suggested using the older crimp F connectors in lieu of compression fittings. I have done both in my testing and am able to get a good connection with both. Using Joels suggestion, Ill be remaking the splice where the coax was crushed hopefully this afternoon before the snow comes. I did speak to Lee at Hi-Z yesterday and he warned me about substandard quality F double females. He has had terrible problems with them. Special thanks to you all for helping me especially Joel, W3RFC and Roger, N1RJ who sent me data sheets for F connectors. Merry Christmas, Happy Holidays and all the best for 2013 Craig Clark K1QX QX Electronics PO Box 209 107 Fitzgerald Rd Rindge NH 03461 (603) 899-6959 office (603) 520 6577 cell ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
At 08:25 AM 12/15/2012, Craig Clark wrote: I did speak to Lee at Hi-Z yesterday and he warned me about substandard quality F double females. He has had terrible problems with them. Which brands/types are the good ones? Maybe some of mine need replacing... BTW, I don't think I've ever met a substandard double F female or a substandard double D, for that matter. ;-) 73, Charles - K5ZK ___ Topband reflector - topband@contesting.com
Re: Topband: The Idiot's Guide To Bi-Directional Two-Wire BeverageConstruction...
Hi Guys, Many thanks to one all for sharing your ideas experiences with the two-wire bi-directional Beverage antenna with me...it's quite obvious that there's a wealth of know-how and experience out there in such matters. The jury is still out here re. the antenna's adoption into VE3CUI - VE3XZ: I already have a 1500' south-terminated Beverage, 50% (or more) of which crosses over some very wet, low-lying marshy land in my back 40 (including a pond). I guess because of the good ground afforded by this reality, the Beverage can't hold a candle to my K9AY loop when temperatures are above freezing...but when ambient air is below 32F for more than a couple of days, the Beverage here starts to come into its own. If I was to try a bi-directional two-wire affair, I'd want to keep it the minimum recommended length---and that would mean that its entire run would have wet soil beneath it... Oh well, as the saying goes, you can't have enough antennas for 160...and even if the system was useable only on those below-freezing days, it might still be a worthwhile project to undertake, such that my ability to copy the JA stations might be enhanced (the whole reason as to why I'm even thinking of this)... ~73~ de Eddy VE3CUI - VE3XZ ___ Topband reflector - topband@contesting.com
Re: Topband: PE coated RG6
Craig, what does lateral mean here - parallel to or perpendicular to the length of the cable? 73, Pete N4ZR Check out the Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com. For spots, please go to your favorite ARC V6 or VE7CC DX cluster node. On 12/15/2012 9:25 AM, Craig Clark wrote: He suggested doing the standard cable prep as you would do for PVC. He then suggested two ½ lateral cuts in to the PE at the 12 and 6 positions and then push the connector on to the cable. Eureka! ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
That is quite an improvement. I had to have dropped the base impedance from 400 ohms to 40 ohms for it to do that. Dave WX7G On Fri, Dec 14, 2012 at 1:12 PM, Carl k...@jeremy.mv.com wrote: A ground screen mesh extending out at least 25' from the base would reduces losses considerably since just 10-20 radials has little effect. At a prior QTH, going from 100 radials of 60-130' to spokes of 4' x 50' rabbit wire mesh on top of them made the difference between also ran and pileup busting on 160. Id call that at least 10dB in anybodys book. My soil was like beach sand altho 20 miles from the ocean; likely leftover from the iceage roll back. - Original Message - From: David Michael Gaytko // WD4KPD wd4...@suddenlink.net To: topband@contesting.com Sent: Friday, December 14, 2012 2:04 PM Subject: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. david/wd4kpd -- God's law is set in stone..everything else is negotiable. __**_ Topband reflector - topband@contesting.com - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1430 / Virus Database: 2634/5459 - Release Date: 12/14/12 __**_ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: Optimal radial wire type and gauge?
Read the N6LF radial papers and you will see that 1/8 wavelength radials are about as good as one can do. I use #14 stranded copper THHN wire because it is easy to work with. But how good can we get? For a 30' base loaded vertical I have 90 radials having an average length of 18 ft. The ground loss is 5 ohms, which is less than the loading coil loss. If I were to install 120 quarter wavelength radials I would gain 2 dB. Dave WX7G ___ Topband reflector - topband@contesting.com
Re: Topband: Fw: GAP VERTICAL QUESTION
Mike that QTH looks alot like the Great Salt Lake of Utah where I have operated a few 160 meter 'tests running a balloon vertical. Dave WX7G On Fri, Dec 14, 2012 at 9:52 AM, Michael Tope w...@dellroy.com wrote: On 12/13/2012 3:14 PM, Tom W8JI wrote: Somehow they thought moving the feedpoint eliminated the need for radials with an electrically short antenna, when the real mechanism was a 1/2 wave vertical was converted to a 1/4 wave groundplane 1/4 wave above ground and it only got a tiny bit weaker. The groundplane still had 8 radials, but they were hundreds of feet in the air. There was some more stuff about offsetting the feedpoint in that handout, but nothing that remotely applied to a fractional wavelength vertical just sitting on the dirt with a few radials laying directly on the lawn. They got rid of lossy traps and loading coils by using even lossier coax and some folded wires for a loading system. This is all why, as frequency increases and the current and voltage moves up the antenna, the GAP on most bands isn't terribly bad. This also why it is a real dog of an antenna on 160 and 80, where it is very short electrically, has no ground system, has an exceptionally poor loading method, and where it folds the radiator back and forth which suppresses radiation resistance. This is why a ten foot mobile antenna can tie it or beat it on 160, and why it is reasonably on par with anything else on most bands above 80 meters. 73 Tom I got hold of a brand new voyager about 7 years ago. The first thing I did was throw away all that yellow coax stuffed inside the bottom half. The fiberglass GAP for the elevated feed point makes a nice insulator for a center loading coil. Then I added some top hat wires with dimensions per WX7G's recommendation and fed the antenna from the bottom as a standard ground mounted vertical with a bunch of radials. For 80 meters, I put a short yard arm at the top with a pulley and hung a wire in parallel with the aluminum radiator. For only being 45ft tall this antenna has worked surprisingly well. I've since lengthened it to 56ft and added an additional parallel wire for 40 meters. I use an Ameritron RCS-4 remote switch at the base to select between 160 or 80/40 (the 80 and 40 meter vertical wires are tied together). I use a 50 to 12.5 ohms Unun on the 160 side to raise the feedpoint Z up to 50 ohms. With all these modifications done in haste before various contests it aint pretty to look at, but it does seem to hold its own against folks with shunt-fed towers and inverted-Ls (at least the ones who don't use overly active antenna tuners :-) ). Here are some pictures of it when I took a trip to one of the dry lake beds north of here: http://www.dellroy.com/W4EF's-**Ham-Radio-Page/CQ160/2006.htmhttp://www.dellroy.com/W4EF's-Ham-Radio-Page/CQ160/2006.htm 73, Mike W4EF... __**_ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
Hi, Tom Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 14, 2012 2:24 PM To: David Michael Gaytko // WD4KPD; topband@contesting.com Subject: Re: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. Only if the original ground system is a meager system with significant loss. At my QTH on 40 meters, 4 elevated radials at 6 feet above ground were about equal to 12-15 radials in the earth. That would be like 4 radials 24 feet above earth on 160. The difference between them was the elevated radials only worked OK on one or two bands (like 40 and 15), while the buried wires were reasonably good on 160-10 meters, out of view, and protected for lightning. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. Since the antenna is an all band antenna, I don't think I would use a resonant radial. I'd just bury as many radials as I could as long and straight as possible, and enjoy all the bands. If you had 10-20 radials 60 feet or more long, it would be tough to make any improvement on lower bands. If you use a resonant radial system, it really should be ground isolated. That complicates things. This 10-20 loss thing, at least to me, appears to be based on anecdotal unconfirmed opinions. Like deer whistles on cars. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: Optimal radial wire type and gauge?
Well, Carl Your thoughts on radials are pretty much like mine! For those of us with limited space, another way to get the 130' elevated radials into limited space is to bend them. I've had really good success on 160 by doing that under and inverted L (about 70-80 feet vertical) I try to arrange to get the first bend out 60-70' from the base of the inverted L. Works pretty well! What helped me the most on 160 and 80 was when I built KAZ style terminated loop with a preamp for a receiving antenna! Suddenly I could HEAR stations on 160 that I didn't even know were there! It also worked very well as a receive antenna on 80, 40 and 30m! Sure helped a lot on my modest city lot!! (With too many tall trees!) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Friday, December 14, 2012 10:41 AM To: Rick Kiessig; topband@contesting.com Subject: Re: Topband: Optimal radial wire type and gauge? I use whatever I can find at the lowest cost which has been mostly #16 and 18 stranded and insulated in 500-1000' reels at a local surplus shop. Ive even used #22 when the other wasnt on hand and it was a weekend. With the current split thru a sufficient number of wires there shouldnt be any unecessary loss. You can also run a thicker wire for the first 50' of so where the current is highest and then splice in the smaller wire. This may be of interest when having to buy new wire at retail cost. There has been very little breakage here from storm damage over the decades since the wires just lay on the branches and are not tied off tight. The sine wave droop is a good way to get 130' of wire in less horizontal space (-; Carl KM1H - Original Message - From: Rick Kiessig kies...@gmail.com To: topband@contesting.com Sent: Friday, December 14, 2012 9:29 AM Subject: Topband: Optimal radial wire type and gauge? The recent talk about optimizing the number of radials has me wondering about the optimal type and gauge for radial wire. I've been using #14 stranded, insulated copper, but for no reason other than it's readily available in 500 ft spools at a decent price. With the cost of copper being so high these days, is there a better choice? If so, how do we know it's really better? And is there an easy way to trade off cost vs. effectiveness? I can't use mesh at my QTH, so I need to stay with actual wire. 73, Rick ZL2HAM ___ Topband reflector - topband@contesting.com - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1430 / Virus Database: 2634/5459 - Release Date: 12/14/12 ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: Fw: GAP VERTICAL QUESTION
Wow, Dave! That sounds great!! Could you support a vertical 1/2 wave for 160 with a balloon? You could end -feed it at the base through a 1/4 wave of 450 ohm ladder line and it would be a FEARSOME 160 antenna! And the whole radial issue goes away!! I've operated a vertical 1/2 wave for 40m this way with GREAT success! Even added a reflector and director to make a full-size vertical 3-element yagi for 3Y0 and SE Asia on the evening 150 degree LP - Great DX antenna! Worked Bouvet first call in a HUGE east coast evening pile-up! :-) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of DAVID CUTHBERT Sent: Saturday, December 15, 2012 10:59 AM To: Michael Tope Cc: topband@contesting.com Subject: Re: Topband: Fw: GAP VERTICAL QUESTION Mike that QTH looks alot like the Great Salt Lake of Utah where I have operated a few 160 meter 'tests running a balloon vertical. Dave WX7G On Fri, Dec 14, 2012 at 9:52 AM, Michael Tope w...@dellroy.com wrote: On 12/13/2012 3:14 PM, Tom W8JI wrote: Somehow they thought moving the feedpoint eliminated the need for radials with an electrically short antenna, when the real mechanism was a 1/2 wave vertical was converted to a 1/4 wave groundplane 1/4 wave above ground and it only got a tiny bit weaker. The groundplane still had 8 radials, but they were hundreds of feet in the air. There was some more stuff about offsetting the feedpoint in that handout, but nothing that remotely applied to a fractional wavelength vertical just sitting on the dirt with a few radials laying directly on the lawn. They got rid of lossy traps and loading coils by using even lossier coax and some folded wires for a loading system. This is all why, as frequency increases and the current and voltage moves up the antenna, the GAP on most bands isn't terribly bad. This also why it is a real dog of an antenna on 160 and 80, where it is very short electrically, has no ground system, has an exceptionally poor loading method, and where it folds the radiator back and forth which suppresses radiation resistance. This is why a ten foot mobile antenna can tie it or beat it on 160, and why it is reasonably on par with anything else on most bands above 80 meters. 73 Tom I got hold of a brand new voyager about 7 years ago. The first thing I did was throw away all that yellow coax stuffed inside the bottom half. The fiberglass GAP for the elevated feed point makes a nice insulator for a center loading coil. Then I added some top hat wires with dimensions per WX7G's recommendation and fed the antenna from the bottom as a standard ground mounted vertical with a bunch of radials. For 80 meters, I put a short yard arm at the top with a pulley and hung a wire in parallel with the aluminum radiator. For only being 45ft tall this antenna has worked surprisingly well. I've since lengthened it to 56ft and added an additional parallel wire for 40 meters. I use an Ameritron RCS-4 remote switch at the base to select between 160 or 80/40 (the 80 and 40 meter vertical wires are tied together). I use a 50 to 12.5 ohms Unun on the 160 side to raise the feedpoint Z up to 50 ohms. With all these modifications done in haste before various contests it aint pretty to look at, but it does seem to hold its own against folks with shunt-fed towers and inverted-Ls (at least the ones who don't use overly active antenna tuners :-) ). Here are some pictures of it when I took a trip to one of the dry lake beds north of here: http://www.dellroy.com/W4EF's-**Ham-Radio-Page/CQ160/2006.htmhttp://w ww.dellroy.com/W4EF's-Ham-Radio-Page/CQ160/2006.htm 73, Mike W4EF... __**_ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
I did speak to Lee at Hi-Z yesterday and he warned me about substandard quality F double females. He has had terrible problems with them. In what respect are they sub-standard? What kind of problems? There is so little that could be defective if the center conductor of the coax is the right size to fit the double-female coupler. Bob VE7BS ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
On 12/15/2012 6:52 AM, Charles Bibb - K5ZK wrote: Which brands/types are the good ones? Amphenol, Amphenol, and Amphenol. Also, the old MIL-spec stuff that can be found at most hamfests when OTs clean out their basements. The shiny new connectors and adapters sold by vendors at hamfests are junk -- the center conductors are flimsy, often no more than springs. I've had cheap connectors fall apart mechanically, the dielectric of connectors intended for soldering will sometimes melt, and so on. These junk connectors go intermittent, or overheat with power. 73, Jim K9YC ___ Topband reflector - topband@contesting.com
Topband: PE Coated RG6
Pete Lateral or along the axis of the coax. I was confused too at first when Joel told me what to do. Craig Craig Clark K1QX QX Electronics PO Box 209 107 Fitzgerald Rd Rindge NH 03461 (603) 899-6959 office (603) 520 6577 cell ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
I also have a 40M GP with 4 elevated resonant radials 6 above the ground. I will be putting up a vertical dipole for 40M center fed with a choke balun for comparison on DX and will compare with the RBN and see what I learn. Has anyone on the forum tested these two 40M antennas using the reverse beacon network ? And if so what were your results ? 73, Bob K6UJ On Dec 15, 2012, at 5:45 AM, Charlie Cunningham wrote: Hi, Tom Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 14, 2012 2:24 PM To: David Michael Gaytko // WD4KPD; topband@contesting.com Subject: Re: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. Only if the original ground system is a meager system with significant loss. At my QTH on 40 meters, 4 elevated radials at 6 feet above ground were about equal to 12-15 radials in the earth. That would be like 4 radials 24 feet above earth on 160. The difference between them was the elevated radials only worked OK on one or two bands (like 40 and 15), while the buried wires were reasonably good on 160-10 meters, out of view, and protected for lightning. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. Since the antenna is an all band antenna, I don't think I would use a resonant radial. I'd just bury as many radials as I could as long and straight as possible, and enjoy all the bands. If you had 10-20 radials 60 feet or more long, it would be tough to make any improvement on lower bands. If you use a resonant radial system, it really should be ground isolated. That complicates things. This 10-20 loss thing, at least to me, appears to be based on anecdotal unconfirmed opinions. Like deer whistles on cars. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Topband: substandard quality F double females
I just posted some pictures of my take on F barrel quality on the Hi-Z website. You might have to refresh the page as it is just now posted. YMMV Lee K7TJR OR http://www.hizantennas.com/f_connector_quality.pdf; ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
Charlie, I will post my results. I had a vertical dipole up before and now am using the 40M GP. The vertical dipole seems to be the best performer for DX but what does that mean, hihi. I thought I would make a table with short path, long path etc. and switch to each antenna using the RBN. Any suggestions on other comparisons or set up ? 73, Bob K6UJ On Dec 15, 2012, at 10:25 AM, Charlie Cunningham wrote: Well, I haven't done such an elaborate test, Bob! But I'd be extremely interested in seeing your results! At present my 40 m GP is down because I needed to clear away the radials for some tree work I still have parallel 40/30 vertical dipoles center fed through a W2DU style current balun. When I had the 40m GP in place. I could do direct comparisons. I was relying mostly on signal reports from 9V1YC other Asians and ease of working him and others in south Asia on the evening south polar path on 40m! Do let us know about your results! Regards, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bob K6UJ Sent: Saturday, December 15, 2012 1:50 PM To: 160 reflector Subject: Re: Topband: raised radials I also have a 40M GP with 4 elevated resonant radials 6 above the ground. I will be putting up a vertical dipole for 40M center fed with a choke balun for comparison on DX and will compare with the RBN and see what I learn. Has anyone on the forum tested these two 40M antennas using the reverse beacon network ? And if so what were your results ? 73, Bob K6UJ On Dec 15, 2012, at 5:45 AM, Charlie Cunningham wrote: Hi, Tom Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 14, 2012 2:24 PM To: David Michael Gaytko // WD4KPD; topband@contesting.com Subject: Re: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. Only if the original ground system is a meager system with significant loss. At my QTH on 40 meters, 4 elevated radials at 6 feet above ground were about equal to 12-15 radials in the earth. That would be like 4 radials 24 feet above earth on 160. The difference between them was the elevated radials only worked OK on one or two bands (like 40 and 15), while the buried wires were reasonably good on 160-10 meters, out of view, and protected for lightning. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. Since the antenna is an all band antenna, I don't think I would use a resonant radial. I'd just bury as many radials as I could as long and straight as possible, and enjoy all the bands. If you had 10-20 radials 60 feet or more long, it would be tough to make any improvement on lower bands. If you use a resonant radial system, it really should be ground isolated. That complicates things. This 10-20 loss thing, at least to me, appears to be based on anecdotal unconfirmed opinions. Like deer whistles on cars. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: GAP Vertical Question
From: charlie-cunning...@nc.rr.com Could you support a vertical 1/2 wave for 160 with aballoon? You could end -feed it at the base through a 1/4 wave of 450 ohm ladder line and it would be a FEARSOME 160 antenna! And the whole radial issue goes away!! I've operated a vertical 1/2 wave for 40m this way with GREAT success!... Probably would be a great antenna as long as the bottom end is elevated well above ground, basically forming a vertically oriented end-fed zepp, something that might actually be feasible with balloon support if the winds are calm. But feeding a half wave vertical with the base near the ground still results in substantial ground losses without a radial system. True, it may be self-resonant and not depend on the ground plane to supply the missing half, but with the presence of lossy earth in the close vicinity of the radiating element, much of the rf power is wasted warming the earthworms, as the earth and its resistive loss provides the majority the return path of rf currents to the antenna base. Another way of looking at it is to think of the ground radial system as a highly conductive shield inserted between the lossy earth and the radiating antenna, carrying the return currents while by-passing most of the ground resistance in the return path. Don k4kyv ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
Amphenol F connectors? Whoah! 73, Pete N4ZR Check out the Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com. For spots, please go to your favorite ARC V6 or VE7CC DX cluster node. On 12/15/2012 12:35 PM, Jim Brown wrote: On 12/15/2012 6:52 AM, Charles Bibb - K5ZK wrote: Which brands/types are the good ones? Amphenol, Amphenol, and Amphenol. Also, the old MIL-spec stuff that can be found at most hamfests when OTs clean out their basements. The shiny new connectors and adapters sold by vendors at hamfests are junk -- the center conductors are flimsy, often no more than springs. I've had cheap connectors fall apart mechanically, the dielectric of connectors intended for soldering will sometimes melt, and so on. These junk connectors go intermittent, or overheat with power. 73, Jim K9YC ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: GAP Vertical Question
Don, a 36 helium balloon filled to 32 is enough to lift 130' of #26 wire in no wind. It doesn't take much wind to blow it horizontal. A half wave vertical suffers more as it is blown down so I think it's best to fly 130' at the most. Flying the balloon from a 40' or taller mast would allow the 130' vertical to become an inverted-L as the wind picks up. Mounted 100' out from the shore at the Salt Lake the ground loss is virtually zero. The water depth is 6 at that point. In the ARRL 160 meter 'test this year the balloon blew into a sharp bush and perished. That may be the last balloon I fly at the lake and a 50' base loaded vertical will take its place. Given that a half wave vertical has a base impedance of over 1000 ohms and a single ground rod in dirt is 100 ohms at most not a single radial is needed to obtain close to 100% radiation efficiency. Dave WX7G ___ Topband reflector - topband@contesting.com
Re: Topband: GAP Vertical Question
On 12/15/2012 12:03 PM, Donald Chester wrote: From: charlie-cunning...@nc.rr.com Could you support a vertical 1/2 wave for 160 with aballoon? You could end -feed it at the base through a 1/4 wave of 450 ohm But feeding a half wave vertical with the base near the ground still results in substantial ground losses without a radial system. Don k4kyv And this statement is based on what? Publications, measurements, modeling? I have built a number of 1/2 wave verticals without radials and compared them to 1/4 wave verticals with radials. They are indistinguishable in performance and certainly do not exhibit substantial ground losses AFAIK. The PAR electronics 1/2 wave end fed antenna seems to have a good reputation, unlike some GAP verticals. However, I don't recommend feeding it through 1/4 wave of 450 ohm open wire line. I just use an LC matching network. Rick N6RK ___ Topband reflector - topband@contesting.com
Re: Topband: GAP Vertical Question
But feeding a half wave vertical with the base near the ground still results in substantial ground losses without a radial system. Don k4kyv And this statement is based on what? Publications, measurements, modeling? I have built a number of 1/2 wave verticals without radials and compared them to 1/4 wave verticals with radials. They are indistinguishable in performance and certainly do not exhibit substantial ground losses AFAIK. The PAR electronics 1/2 wave end fed antenna seems to have a good reputation, unlike some GAP verticals. I know you already know this Rick, but everyone else should be reminded ***EVERY*** end fed antenna requires some type of ground system. In the PAR antenna, the coax shield is a counterpoise, just like in the end-fed Zepp the ladder line is a counterpoise that radiates. While some seem to have created a new physics that a simple single wire counterpoise can be non-radiating, there always has to be some fairly strong external induction field associated with end feeding an antenna. It can be predominately electric or magnetic, but rest assured there is a return path providing that second terminal for the feedpoint. The PAR antenna gets away with a sloppy feed system because most users run low power, and the shield of the coax becomes the counterpoise. In the real world loss can be all over the place depending on the exact system, including feedline length and grounding. While it is true that I^2 R feedpoint losses are not nearly as bad as a quarter wave Marconi, we exchange the strong current issues of a high current feed with high voltages and a strong electric field. This is why the end-fed Zepp, even in perfect construction form, has terrible local RFI issues even though feeder EM radiation is minimal. If you do a near field measurement of a perfect Zepp, the electric field intensity is off the charts around the feeder. If the feeder is the wrong grounding for common mode, the common mode current can be terrible and the electric field greatly drops. The feeder can radiate as much as the antenna, or more, with a simple ground change! This also applies to the PAR. Even with a half-wave, we have to have some common sense about what we do at the feedpoint and feedline. There are still displacement currents, and if we get rid of that pesky ground current we do that by trading for a pesky electric field. :-) There are enough well-spoken salesmen selling people magic, and they don't need our help. :-) 73 Tom ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) I'd expect that. When we tested radials on 40M we measured field strength, and that was pretty much the point where not much else could significantly change. However, given the choice of four elevated radials at six feet (equivalent perhaps of 24 feet height on 160, but who knows if it really scales or not) or 12-15 in the ground (and who knows if that also scales to 160), I'd use the buried or laid on earth radials. :-) 73 Tom ___ Topband reflector - topband@contesting.com
Re: Topband: Optimal radial wire type and gauge?
There is no magic about 120 radials, and long before 120 radials are reached the increase in field strength pretty much stops. At my house around 30 radials or so, about 1/4 wave long, go flat on efficiency increase on 160 meters. I could have a million radials and it would be insignificantly different than 30 radials when they are 1/4 wave long here. I found this by measuring field strength, and I also found feed resistance change did NOT necessarily track the field strength changes. Good luck on using base impedance to determine effiency changes! In a 40 meter test, for example, one ground system provided 35-40 ohms of feed resistance and another different system that provided almost 60 ohms of feedpoint resistance had equal field strength. I think N6RK and others have measured the same. 73 Tom - Original Message - From: DAVID CUTHBERT telegraph...@gmail.com To: Rick Kiessig kies...@gmail.com Cc: topband@contesting.com Sent: Saturday, December 15, 2012 10:49 AM Subject: Re: Topband: Optimal radial wire type and gauge? Read the N6LF radial papers and you will see that 1/8 wavelength radials are about as good as one can do. I use #14 stranded copper THHN wire because it is easy to work with. But how good can we get? For a 30' base loaded vertical I have 90 radials having an average length of 18 ft. The ground loss is 5 ohms, which is less than the loading coil loss. If I were to install 120 quarter wavelength radials I would gain 2 dB. Dave WX7G ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
That is quite an improvement. I had to have dropped the base impedance from 400 ohms to 40 ohms for it to do that. Things are often magic when we rely on feelings or emotions to measure decibels. ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
I am very interested in the comparison. I am almost daily on 40m SSB at about 15:00 for LP with a couple of friends. The San Diego area is also good for SP a bit later. RBNs in Europe most of the time will probably not copy you on the LP. Most RBN use poor antennas and the band is still crowded with European contacts. 73 Peter, DJ7WW -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bob K6UJ Sent: Samstag, 15. Dezember 2012 20:58 To: Charlie Cunningham Cc: '160 reflector' Subject: Re: Topband: raised radials Charlie, I will post my results. I had a vertical dipole up before and now am using the 40M GP. The vertical dipole seems to be the best performer for DX but what does that mean, hihi. I thought I would make a table with short path, long path etc. and switch to each antenna using the RBN. Any suggestions on other comparisons or set up ? 73, Bob K6UJ On Dec 15, 2012, at 10:25 AM, Charlie Cunningham wrote: Well, I haven't done such an elaborate test, Bob! But I'd be extremely interested in seeing your results! At present my 40 m GP is down because I needed to clear away the radials for some tree work I still have parallel 40/30 vertical dipoles center fed through a W2DU style current balun. When I had the 40m GP in place. I could do direct comparisons. I was relying mostly on signal reports from 9V1YC other Asians and ease of working him and others in south Asia on the evening south polar path on 40m! Do let us know about your results! Regards, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bob K6UJ Sent: Saturday, December 15, 2012 1:50 PM To: 160 reflector Subject: Re: Topband: raised radials I also have a 40M GP with 4 elevated resonant radials 6 above the ground. I will be putting up a vertical dipole for 40M center fed with a choke balun for comparison on DX and will compare with the RBN and see what I learn. Has anyone on the forum tested these two 40M antennas using the reverse beacon network ? And if so what were your results ? 73, Bob K6UJ On Dec 15, 2012, at 5:45 AM, Charlie Cunningham wrote: Hi, Tom Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 14, 2012 2:24 PM To: David Michael Gaytko // WD4KPD; topband@contesting.com Subject: Re: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. Only if the original ground system is a meager system with significant loss. At my QTH on 40 meters, 4 elevated radials at 6 feet above ground were about equal to 12-15 radials in the earth. That would be like 4 radials 24 feet above earth on 160. The difference between them was the elevated radials only worked OK on one or two bands (like 40 and 15), while the buried wires were reasonably good on 160-10 meters, out of view, and protected for lightning. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. Since the antenna is an all band antenna, I don't think I would use a resonant radial. I'd just bury as many radials as I could as long and straight as possible, and enjoy all the bands. If you had 10-20 radials 60 feet or more long, it would be tough to make any improvement on lower bands. If you use a resonant radial system, it really should be ground isolated. That complicates things. This 10-20 loss thing, at least to me, appears to be based on anecdotal unconfirmed opinions. Like deer whistles on cars. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: raised radials
One thing I've wondered: are elevated radials more likely to pickup local QRN than those on the ground, or buried? The on-ground 160M loop antennas I've used for reception seemed quieter here than those that were elevated 15-20'. Before my 160 tree blew down this Fall and took the Inv-L antenna with it, I could walk around with an AM radio next to the 8 elevated tuned radials (4' at the antenna base angling up to ~15' in the trees) and pick up local hash and some minor AM BCB. Some radials were 'louder' than others, mainly those closest to potential noise sources like the AC power line or the house meter loop. I never tried that with on-ground radials as I had none to compare them with. The antenna base was ungrounded and fed through a custom wound UN-UN followed by a DXE VFCC-H10-A choke. There was no BCB in the shack end of the coax where I had slipped on 10 Type 31 ferrite beads, but there was still city QRN of course. 73, Gary NL7Y ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
Which brands/types are the good ones? Maybe some of mine need replacing... BTW, I don't think I've ever met a substandard double F female or a substandard double D, for that matter. ;-) 73, Charles - K5ZK Charles, I'm not sure which brands are bad, but I've been pretty lucky and not run into any. It doesn't surprise me, with Chinese manufacturing quality, that poor connectors are starting to appear. I think there is a risk people might go overboard on connectors based on a few substandard connectors. I started dealing with F connectors back in the 1970's. I was systems engineer at a company that had many dozens or perhaps a hundred or so MATV and CATV systems. With hundreds of thousands of connectors, we could not tolerate even a small fraction of a percent connector failures. All of the connectors we used, and I'm sure this applied throughout the industry, were tin contacts. The last thing we would use was gold, because gold would aggravate something we called fretting corrosion in contact with copper clad steel, tinned, or CCA cables. Tin plating was excellent under dry circuit conditions, like CATV drop feeds, where no significant current flowed through the contact. Tin plated contacts had to be protected from oxidation by a grease. The grease also allows the connectors to be reused over and over without ruining the tin. We found a 100% pure silicon dielectric grease best. We used a product by GE back then, and I use something called automotive tune up grease now. It looks and smells identical. Outside of lightning I have no problems with hundreds of F connections in my system. ALL connectors I have taken apart over the past 40 years have had spring contacts. This includes trunk cable connectors. The spring is a two piece deal that is sort of double V shaped from the side with one long leg. The wire pushes the V point's apart. A good connection requires a pretty good spring force. If you insert a piece of dry center conductor in the contact, you should be able to feel the female grabbing the wire. It can't feel like a zero insertion force connection, or you will have problems. I would never use gold unless it was against gold. Tin is good for tin to tin, tin to silver, and tin to copper. I know of CATV systems that installed gold plated connectors and had to go out and remove them. I think Comcast got into that once. Besides that, some gold connectors are not even real gold. They are just gold colored crap. My suggestion is to ask advice from and use what the CATV industry uses and has used for years. I know everyone thinks gold is magic, but it can be a real headache even in cases where it really is gold. The single most important thing in any connection is to NOT let a stray stand get loose and short the connector, to prep the ends properly including folding or not folding the shield as required by the cable and connector, and to lube the connector with something to keep air and moisture out. I have many hundreds of F's in my system, and I'm not particularly choosey about picking certain brands of females so long as they pass the insertion force and pull test (they have to have a definite grabbing friction when dry) and are tinned center contacts. The last thing you will find around here are gold connectors, unless they mate to another gold contact. I also ALWAYS lube the connector with silicon dielectric compound. 73 Tom ___ Topband reflector - topband@contesting.com
Topband: vertical dipole vs vertical with elev radials
Charlie, Yeah I see what you mean they each have a different take off angle lobe. I will run a run a plot with EZNEC of each and see what they show. I have changed/ started a new subject title for this activity we are discussing, we have taken off in a separate direction than the original thread. It will be interesting to see what we can find out. 73, Bob K6UJ On Dec 15, 2012, at 2:42 PM, Charlie Cunningham wrote: Well, to me, Bob, the 1/2 wave 40m vertical seemed to be better - but not by much! At the same time, though, it's worth noting that the base of the GP - and therefore, antenna current maximum, was only 6-8 ft high whereas the current maximum of the 1/2 wave 40m vertical was at about 38 ft and more clear of obstructions. Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bob K6UJ Sent: Saturday, December 15, 2012 2:58 PM To: Charlie Cunningham Cc: '160 reflector' Subject: Re: Topband: raised radials Charlie, I will post my results. I had a vertical dipole up before and now am using the 40M GP. The vertical dipole seems to be the best performer for DX but what does that mean, hihi. I thought I would make a table with short path, long path etc. and switch to each antenna using the RBN. Any suggestions on other comparisons or set up ? 73, Bob K6UJ On Dec 15, 2012, at 10:25 AM, Charlie Cunningham wrote: Well, I haven't done such an elaborate test, Bob! But I'd be extremely interested in seeing your results! At present my 40 m GP is down because I needed to clear away the radials for some tree work I still have parallel 40/30 vertical dipoles center fed through a W2DU style current balun. When I had the 40m GP in place. I could do direct comparisons. I was relying mostly on signal reports from 9V1YC other Asians and ease of working him and others in south Asia on the evening south polar path on 40m! Do let us know about your results! Regards, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Bob K6UJ Sent: Saturday, December 15, 2012 1:50 PM To: 160 reflector Subject: Re: Topband: raised radials I also have a 40M GP with 4 elevated resonant radials 6 above the ground. I will be putting up a vertical dipole for 40M center fed with a choke balun for comparison on DX and will compare with the RBN and see what I learn. Has anyone on the forum tested these two 40M antennas using the reverse beacon network ? And if so what were your results ? 73, Bob K6UJ On Dec 15, 2012, at 5:45 AM, Charlie Cunningham wrote: Hi, Tom Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 14, 2012 2:24 PM To: David Michael Gaytko // WD4KPD; topband@contesting.com Subject: Re: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. Only if the original ground system is a meager system with significant loss. At my QTH on 40 meters, 4 elevated radials at 6 feet above ground were about equal to 12-15 radials in the earth. That would be like 4 radials 24 feet above earth on 160. The difference between them was the elevated radials only worked OK on one or two bands (like 40 and 15), while the buried wires were reasonably good on 160-10 meters, out of view, and protected for lightning. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. Since the antenna is an all band antenna, I don't think I would use a resonant radial. I'd just bury as many radials as I could as long and straight as possible, and enjoy all the bands. If you had 10-20 radials 60 feet or more long, it would be tough to make any improvement on lower bands. If you use a resonant radial system, it really should be ground isolated. That complicates things. This 10-20 loss thing, at least to me, appears to be based on anecdotal unconfirmed opinions. Like deer whistles on cars. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Topband: vertical dipole vs vertical with elev radials
Jim, I will post the results here on the reflector. Note the changed subject for this thread to cover this activity. We have drifted away from the original thread. Yes, please share your results on the 80 dipole and inverted L ! The RBN is a great tool available to us for testing our antennas. If anyone can offer advice on how to do the best job of setting up and collecting the data from the RBN please jump in. One thing I know is to collect as much test data as we can so our results aren't based upon only one or two tests. 73, Bob K6UJ On Dec 15, 2012, at 1:03 PM, Jim Koshmider wrote: Hi, Bob - If possible, I would like to be added to your list so I can receive info on the result of your tests. I will soon be running similar tests between an 80 meter center-fed dipole and an inverted L, and will be happy to share the results. Tnx es 73, Jim, K8OZ From: Bob K6UJ k...@pacbell.net To: 160 reflector topband@contesting.com Sent: Saturday, December 15, 2012 11:50 AM Subject: Re: Topband: raised radials I also have a 40M GP with 4 elevated resonant radials 6 above the ground. I will be putting up a vertical dipole for 40M center fed with a choke balun for comparison on DX and will compare with the RBN and see what I learn. Has anyone on the forum tested these two 40M antennas using the reverse beacon network ? And if so what were your results ? 73, Bob K6UJ On Dec 15, 2012, at 5:45 AM, Charlie Cunningham wrote: Hi, Tom Well, I also used a 40m GP with 4 elevated resonant radials about 6' above ground and I worked an awful lot of really good DX with it!! I found it to be about equal to my half-wave vertical dipole for 40m. (Center fed through a home-made 1:1 W2DU style current balun) Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Friday, December 14, 2012 2:24 PM To: David Michael Gaytko // WD4KPD; topband@contesting.com Subject: Re: Topband: raised radials the more i read, it seems raised radials are a fairly easy way to raise the effeciancy of a short vertical. Only if the original ground system is a meager system with significant loss. At my QTH on 40 meters, 4 elevated radials at 6 feet above ground were about equal to 12-15 radials in the earth. That would be like 4 radials 24 feet above earth on 160. The difference between them was the elevated radials only worked OK on one or two bands (like 40 and 15), while the buried wires were reasonably good on 160-10 meters, out of view, and protected for lightning. i have a hy-gain 18ht with base loading. can i use these raised radials with this antenna, and if so how to do it. it is impossible to raise the whole antenna to get the base off the ground. Since the antenna is an all band antenna, I don't think I would use a resonant radial. I'd just bury as many radials as I could as long and straight as possible, and enjoy all the bands. If you had 10-20 radials 60 feet or more long, it would be tough to make any improvement on lower bands. If you use a resonant radial system, it really should be ground isolated. That complicates things. This 10-20 loss thing, at least to me, appears to be based on anecdotal unconfirmed opinions. Like deer whistles on cars. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: GAP Vertical Question
On 12/15/2012 5:13 PM, Charlie Cunningham wrote: Well, Rick, for me, the 450 ohm line was cheap, available and weatherproof! The trouble with the 450 ohm line is that you have a balanced line with an unbalanced load. You would like to put a balun or common-mode choke at the antenna end, but that is impractical. Thus the line will have substantial radiation and probably will warm the worms. Also, 450 ohm window line is NOT really weatherproof, as has been reported by reliable sources. Maybe you used true OWL which would be. Rick N6RK ___ Topband reflector - topband@contesting.com
Re: Topband: J6
Not 160 but I worked him on 12M on Dec 5 Gary KA1J Re: J6/N7QT I worked him around 02z on the 10th on 80 CW and asked about 160 and he said 'probably tomorrow' but I never heard him that night and I stayed home from an event my wife wanted to go to as well to look for him ... ouch He was on 30 m though. I heard somewhere that they had to share an antenna between 80 and 160 and could do only one band at a time. I heard a local op on the 2meter FM repeater who was on previous Buddipole expeditions, who spoke of this one as if it had already finished. This was last night here. J6 would be new on topband here. I had not heard of any of the other J6 'buddipole' ops being on 160. 73 Bob k2euh Carl Jonsson carl.jonss...@gmail.com wrote: Anybody hrd J6 /N7QT on 160? Heard him on 80 on Dec 11th, but since then nothing. Any news? 73 Carl SM6CPY ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
Oh really? What about CCS against gold with silicone dielectric compound to seal out moisture, Tom? I haven't used those gold-plated connectors yet. Maybe I should return them for a refund? 73, Mike www.w0btu.com On Sat, Dec 15, 2012 at 8:37 PM, Tom W8JI w...@w8ji.com wrote: The last thing we would use was gold, because gold would aggravate something we called fretting corrosion in contact with copper clad steel, tinned, or CCA cables. ... I would never use gold unless it was against gold. Tin is good for tin to tin, tin to silver, and tin to copper. I know of CATV systems that installed gold plated connectors and had to go out and remove them. ___ Topband reflector - topband@contesting.com
Re: Topband: substandard quality F double females
On 12/15/2012 12:04 PM, Pete Smith N4ZR wrote: Amphenol F connectors? Whoah! Nuts. I didn't read carefully enough. Again. Thanks Pete. I was thinking UHF. 73, Jim K9YC ___ Topband reflector - topband@contesting.com
