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References: [ +from:riel@surriel.com: 65 ]

Total 65 documents matching your query.

21. Re: [TowerTalk] 80/40 coax trap dipole design (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 16 Dec 2010 11:58:30 -0500
That would take care of one of the traps, and keep the antenna from working on 60m... The puzzle is to get an antenna like this (T is trap, X is feedpoint) to work as: - a double L (lazy U) on 160 -
/archives//html/Towertalk/2010-12/msg00283.html (10,103 bytes)

22. Re: [TowerTalk] 160M Inverted L Elev Radials EZNEC Model Wanted (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Wed, 29 Dec 2010 17:19:25 -0500
I've got one better than you - the double L. It takes up even less space than an inverted L with one elevated radial, and has the point of maximum current much higher above ground. In ASCII art, they
/archives//html/Towertalk/2010-12/msg00398.html (8,441 bytes)

23. Re: [TowerTalk] 160M Inverted L Elev Radials EZNEC Model Wanted (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Wed, 29 Dec 2010 18:48:36 -0500
In my case, I simply use #12 THHN wire shot across the very top of a 70' or so tall tree. The top wire runs across a few trees to a tree about 100' away, the bottom wire runs in the same general dire
/archives//html/Towertalk/2010-12/msg00402.html (8,422 bytes)

24. Re: [TowerTalk] Non-sagging antenna elements (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 30 Dec 2010 12:02:54 -0500
I am sure I could model this with NEC. However, I don't think trying that is even worthwhile, because I suspect the pattern distortion from having the wire sag will be negligible compared to the patt
/archives//html/Towertalk/2010-12/msg00444.html (9,533 bytes)

25. Re: [TowerTalk] Aluminum clad wire (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 30 Dec 2010 12:04:51 -0500
My 80 meter loop is built from the 14 ga electric fence aluminum wire bought at TSC. It's been up for well over a year and has survived a few 60mph storms. -- All rights reversed. ___________________
/archives//html/Towertalk/2010-12/msg00445.html (9,447 bytes)

26. Re: [TowerTalk] Fwd: Using aluminum wire [or aluminum clad wire] (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 30 Dec 2010 16:08:31 -0500
I go Al to Cu to get from my 80m loop to my balun. I want some flexibility in the wire that goes to the balun, so I use 14ga stranded THHN copper for the final foot or so (a loop from the center insu
/archives//html/Towertalk/2010-12/msg00460.html (9,591 bytes)

27. Re: [TowerTalk] Fwd: Using aluminum wire [or aluminum clad wire] (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Fri, 31 Dec 2010 13:56:24 -0500
OK, thanks for that info. That is good to know. I do stick each wire all the way into the terminal strip, so they both get squeezed by both of the screws. I hope that tightening the screws as far as
/archives//html/Towertalk/2010-12/msg00486.html (10,581 bytes)

28. Re: [TowerTalk] Recommended Coaxial Surge Protector for HF (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Fri, 31 Dec 2010 21:24:25 -0500
I simply put 3 Mohm in resistors into the balun I built for my 160 vertical. I hope that will stop static from building up :) Other things can take care of real surges (eg. the gas discharge tube sur
/archives//html/Towertalk/2010-12/msg00497.html (7,987 bytes)

29. Re: [TowerTalk] RG 303 (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Sun, 02 Jan 2011 10:49:42 -0500
Small volumes of RG303 seem to be exorbitantly expensive, with several shops charging several dollars per foot. I did find one seller with 75 cents/foot: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
/archives//html/Towertalk/2011-01/msg00008.html (7,063 bytes)

30. Re: [TowerTalk] ground rods and wells (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 06 Jan 2011 18:19:58 -0500
The reason is simple. Current is pushed into one side of the antenna and "pulled out" the other. (to over-simplify things) In-between both sides of the antenna, the current has to travel through what
/archives//html/Towertalk/2011-01/msg00139.html (9,771 bytes)

31. Re: [TowerTalk] ground rods and wells (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 06 Jan 2011 22:15:05 -0500
It's a dramatic oversimplification. I am sure that others can give a more accurate description of what happens, and that still others will misinterpret that more accurate description :) -- All rights
/archives//html/Towertalk/2011-01/msg00141.html (9,094 bytes)

32. Re: [TowerTalk] 80 meter dipole with open sleeve parasitic (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 20 Jan 2011 09:31:04 -0500
I wouldn't think 40m is a wide enough band to need such an open sleeve dipole. On the other hand, it should be possible to mount a 30m parasitic element inside a 40m folded dipole, and get both bands
/archives//html/Towertalk/2011-01/msg00318.html (7,502 bytes)

33. Re: [TowerTalk] vertical antenna question (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 20 Jan 2011 19:30:54 -0500
Your antenna impedance right now will be a sum of the wire resistance (small, lets ignore it), the radiation resistance (Rr) and the ground resistance (Rg). R = Rr + Rg Your radials will "short out"
/archives//html/Towertalk/2011-01/msg00330.html (8,205 bytes)

34. Re: [TowerTalk] Compression-type PL-259s (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Thu, 20 Jan 2011 19:39:55 -0500
I have heard that crimping may be a bad idea with the LMR-400 alike cable that uses copper clad aluminum as the center conductor. The reason stated is that copper and aluminum have different thermal
/archives//html/Towertalk/2011-01/msg00332.html (8,658 bytes)

35. Re: [TowerTalk] Soldering PL-259 (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Fri, 21 Jan 2011 23:09:31 -0500
Even a 40W iron seems to work fine, as long as it has a real heavy tip. Between soldering the different holes I need to turn the LMR-400 around anyway, which gives the iron time to heat back up to a
/archives//html/Towertalk/2011-01/msg00375.html (8,982 bytes)

36. Re: [TowerTalk] Intruder on 3985? (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Wed, 02 Feb 2011 15:49:03 -0500
I suspect you heard Voice of Croatia. No need to report them, as they register their transmissions with the HFCC already. Remember that 3900-3950 is a broadcast band in Asia, and 3950-4000 is a broad
/archives//html/Towertalk/2011-02/msg00040.html (7,497 bytes)

37. Re: [TowerTalk] Inverted V for 160/80 on the same feedline (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Wed, 20 Apr 2011 19:34:01 -0400
There's always the double L antenna by K2LQ, which is not much harder to set up than a V and doesn't require an extensive radial system like a vertical: http://www.yccc.org/Articles/double_l.htm -- A
/archives//html/Towertalk/2011-04/msg00329.html (10,322 bytes)

38. Re: [TowerTalk] Multi-band dipoles (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Fri, 22 Apr 2011 17:00:10 -0400
It works great with ALE, because the radio automatically picks the path with the best propagation. Losing 6dB in the antenna is no big deal, when the radio reduces the propagation losses by 20dB over
/archives//html/Towertalk/2011-04/msg00390.html (10,060 bytes)

39. Re: [TowerTalk] Multi-band dipoles (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Fri, 22 Apr 2011 17:02:56 -0400
There are a few additional reasons why it could be quieter. Specifically, the antenna is a loop (albeit with a resistor), which means it is always electrically symmetrical and less sensitive to coron
/archives//html/Towertalk/2011-04/msg00391.html (8,967 bytes)

40. Re: [TowerTalk] Multi-band dipoles (score: 1)
Author: Rik van Riel <riel@surriel.com>
Date: Sat, 23 Apr 2011 02:07:12 -0400
I think you're right. One reason why in practice loops and t2fds sometimes end up being lower noise, is that people think they can get away with using their dipole without a (proper) balun. A properl
/archives//html/Towertalk/2011-04/msg00399.html (9,059 bytes)


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