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181. [TowerTalk] steppIR as topload (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 9 Feb 2005 19:27:04 -0500
Would it not make sense to contact SteppIR and ask questions about standoff distances of the motor units from the boom, under 160m topload applications, rather than speculate here? My guess is, they
/archives//html/Towertalk/2005-02/msg00285.html (7,540 bytes)

182. [TowerTalk] Knock it off--- vendor abuse (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 9 Feb 2005 19:27:04 -0500
Jeez, guys.... KQ2M has a $130 difference of opinion with a vendor, and has to wash laundry here. And we need to echo it, speculate upon it, and generally support one side or the other? This is not a
/archives//html/Towertalk/2005-02/msg00286.html (7,487 bytes)

183. [TowerTalk] Rohn wasn't perfect-- can we end this please? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 9 Feb 2005 20:08:10 -0500
Guys!!!!~ A few years ago, I bought some new 45G and the bloody stuff wouldn't even nest! One leg was over a half inch out of alignment...and not bent. It was welded that way. I had to have it remanu
/archives//html/Towertalk/2005-02/msg00292.html (8,199 bytes)

184. [TowerTalk] A ground system saga... (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 12 Feb 2005 17:06:18 -0500
I'm not sure I actually believe this, but it's amusing to think about, and no more tedious than some of the recent rants we've had... (Is winter over, yet?) urinate ring. moaning. [Jim Jarvis] N2EA (
/archives//html/Towertalk/2005-02/msg00331.html (8,101 bytes)

185. [TowerTalk] liberating aluminum (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 17 Feb 2005 12:54:35 -0500
Multiple applications of wd40 help. Ultimately, heating the exterior tube quickly with a propane torch may break things free. Particularly if oxidized between the tubes. Using a wrench or vise grips
/archives//html/Towertalk/2005-02/msg00421.html (7,449 bytes)

186. [TowerTalk] What Gerald said.... (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 17 Feb 2005 16:49:50 -0500
As an aluminum supplier, Texas Towers recommends the following procedure in case of stuck aluminum: Your aluminum options are shown at _www.texastowers.com_ (http://www.texastowers.com) . Tnx/73, Ger
/archives//html/Towertalk/2005-02/msg00432.html (7,772 bytes)

187. [TowerTalk] 4square/spitfire alternative (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Feb 2005 05:58:54 -0500
You didn't mention what you have for vertical support, and this may be the dominant deciding factor. If it were me, however, I would look at an array of 4 sloping dipoles on 40...switched at the cent
/archives//html/Towertalk/2005-02/msg00508.html (8,621 bytes)

188. [TowerTalk] FW: 4square/spitfire second thought (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Feb 2005 06:09:17 -0500
An early-morning second thought... In my earlier comment, I suggested an array of dipoles instead, fed per the ARRL handbook through 3/8 wavelength feedlines routed to a center commonpoint feed. Righ
/archives//html/Towertalk/2005-02/msg00509.html (8,036 bytes)

189. Re: [TowerTalk] 4square/spitfire alternative (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Feb 2005 09:30:43 -0500
N4ZR wrote: (full text on bottom) My reply: Pete (TT) I only tried this once, on 75, and had good results. Didn't model it. Didn't fold the ends back, just let the dipoles stretch out, and sag a bit,
/archives//html/Towertalk/2005-02/msg00513.html (13,951 bytes)

190. [TowerTalk] insulated wire as radials and antennas. (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Feb 2005 13:38:11 -0500
W1XT and myself have observed arcing (through 600 volt insulation) when the radials came in contact with each other. -0- To which I have to append...that's 600V @ 60Hz! God knows what it is at 7 MHz.
/archives//html/Towertalk/2005-02/msg00523.html (7,190 bytes)

191. [TowerTalk] SWR Problem with Tri-Bander (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Feb 2005 18:38:35 -0500
If it were balun connections, why would it manifest only on 15 meters? If it were the 15m traps, or one of them on the DE, why wouldn't the current on 20 also heat it, causing a shift there? Still, I
/archives//html/Towertalk/2005-02/msg00536.html (7,418 bytes)

192. [TowerTalk] lighting "umbrella" (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Feb 2005 12:51:30 -0500
Folks, There's an aspect of this that hasn't been touched on, that has to be considered. Let's assume that you have a really good dissipative ground system from said tower. Multiple rods, multiple ra
/archives//html/Towertalk/2005-02/msg00595.html (8,996 bytes)

193. [TowerTalk] foldover antenna bracket design (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Feb 2005 12:56:45 -0500
Is anyone interested in design detail for a bracket which will allow a yagi to remain horizontal, while the tower holding it is lowered to the horizontal? I have pics of a design, and just threw out
/archives//html/Towertalk/2005-02/msg00596.html (7,370 bytes)

194. Re: [TowerTalk] lighting "umbrella" (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Feb 2005 14:00:17 -0500
Hi Gary, In my case, I use clip on ferrite chokes. Type 73, from radioworks. Coax shields are grounded at the SPG. Ferrites isolate the shield exteriors from RF, so the antennas aren't tied together.
/archives//html/Towertalk/2005-02/msg00599.html (12,657 bytes)

195. Re: [TowerTalk] lighting "umbrella" (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Feb 2005 14:03:35 -0500
Actually, Gary, a SINGLE TURN lightning choke will work quite effectively. They're commonly used on AM bcdst towers, to increase the dV at the tower base, and trigger an arc at the tower base lightni
/archives//html/Towertalk/2005-02/msg00600.html (12,248 bytes)

196. [TowerTalk] lightning umbrella (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Feb 2005 15:31:50 -0500
To determine the "cone of protection" that the tower will provide make a ball with a 150 foot radius. Roll that ball on the ground up to the tower until it touches the top of the tower. Everything un
/archives//html/Towertalk/2005-02/msg00604.html (9,279 bytes)

197. [TowerTalk] substandard aluminum? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 1 Mar 2005 10:36:33 -0500
ZF2NT's tale of woe regarding the Titanex vertical raises some interesting questions. Evidently the problem hasn't been solved, and the solution needs to come from the manufacturer. As for the chaps
/archives//html/Towertalk/2005-03/msg00011.html (7,952 bytes)

198. Re: [TowerTalk] substandard aluminum? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 1 Mar 2005 15:26:01 -0500
Telrex: I think there was a period when lighter, stronger aluminum was available, and was used in production. This resulted in different physical resonance conditions, which in turn resulted in prema
/archives//html/Towertalk/2005-03/msg00027.html (9,829 bytes)

199. [TowerTalk] Tela-who? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 2 Mar 2005 19:40:21 -0500
Telrex Corp. Founded by Mike Ercolino in early 50's, Neptune City NJ. made amateur and commercial HF communications antennas, rotors, supports. no longer in business. When the old man ran it, they we
/archives//html/Towertalk/2005-03/msg00072.html (8,024 bytes)

200. [TowerTalk] vertical dipole (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 2 Mar 2005 22:25:29 -0500
My experience with 40m vertical dipoles vs. horizontal dipoles with centers at the same height (50') is that signals inside of 4-5k miles are down by 4-6 dB. Sometimes more. Signals beyond that...out
/archives//html/Towertalk/2005-03/msg00079.html (7,944 bytes)


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