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221. [TowerTalk] crosstalk between beams (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 19 Mar 2005 07:54:46 -0500
Simultaneous operation of yagis on a common boom. Interesting topic. But it has 'bad idea' written all over it. I don't care how much modelling or measuring you do. At best, you'll get a headache. If
/archives//html/Towertalk/2005-03/msg00624.html (7,239 bytes)

222. [TowerTalk] pointing antenna into wind. (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 20 Mar 2005 15:07:45 -0500
Jose, There was an extended thread on a related topic, about two months back, having to do with windload calculation. In fact, greatest windload will probably result from the boom being broadside to
/archives//html/Towertalk/2005-03/msg00681.html (7,838 bytes)

223. [TowerTalk] lightning rods, splineballs, and 1 irons (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 20 Mar 2005 17:50:47 -0500
Recently, I consulted with the cap'n of a large charter sailing vessel, who had posted here concerning lightning protection. He was losing masthead instrument pods due to lightning hits. I recommende
/archives//html/Towertalk/2005-03/msg00693.html (8,116 bytes)

224. [TowerTalk] portable soldering iron (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 21 Mar 2005 18:24:50 -0500
Mark (TT): I think Craig Clark's word was "FUGEDABOUTIT!" To which I will append....how many BTU's can you cram in a double A cell? Further to that, in 10 years in Vermont, I also observed that my ra
/archives//html/Towertalk/2005-03/msg00715.html (7,668 bytes)

225. Re: [TowerTalk] [BULK] - portable soldering iron (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 21 Mar 2005 19:37:26 -0500
NOT enough BTU's, Steve, if you're in a cold climate. I remind you, Steve....a cold day in CA is much like a Spring 'morn in Vermont. In -20....a 12v powered anything is inadequate. \Mike....where in
/archives//html/Towertalk/2005-03/msg00720.html (8,729 bytes)

226. [TowerTalk] corrosion and wear of moving parts (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Mar 2005 20:12:37 -0500
To Gary, who opined that corrosion and wear would render all SteppIR's useless in 5 years, and Brian (n1ik), who responded with the following, edited comments; -0- Gary. Good points. We'll just have
/archives//html/Towertalk/2005-03/msg00755.html (8,462 bytes)

227. [TowerTalk] painting steppIR elements (score: 1)
Author: jimjarvis@comcast.net
Date: Sat, 26 Mar 2005 18:12:17 +0000
Steve's recent post of the pics from the MonstIR install were quite interesting. I wonder what effect painting the fiberglass tubes will have? N2EA _______________________________________________ See
/archives//html/Towertalk/2005-03/msg00843.html (6,710 bytes)

228. [TowerTalk] metal whiskers (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 2 Apr 2005 12:18:41 -0500
I wasn't going to comment on this thread...but I think it's now in order... here's a concise snip of the previous (without attribution), followed by my comments: -0- Whiskers are an issue in reliabil
/archives//html/Towertalk/2005-04/msg00045.html (9,374 bytes)

229. [TowerTalk] 40m KLM (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 3 Apr 2005 16:24:01 -0400
W2RU suggested: In order of preference: 1. Hire KC1XX 2. Hire a crane 3. Disconnect guy wires and lay the tower over in the next windstorm 4. Follow my procedure below -0- To which I'll append...talk
/archives//html/Towertalk/2005-04/msg00104.html (8,133 bytes)

230. [TowerTalk] simultaneous Horizontal and Vertical antennas (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 3 Apr 2005 23:17:01 -0400
TWO POINTS TO BE MADE HERE... First...Jamesnf commented: "Frequently, on 80 meters, they use a four square vertical system and a low dipole yielding potent directional, low angle radition for dx from
/archives//html/Towertalk/2005-04/msg00110.html (8,747 bytes)

231. [TowerTalk] Multiple antennas-- offpointed stacks (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 4 Apr 2005 11:28:18 -0400
W8JI's observations reminded me of some of the doubts I've had, when taking the lower yagi in a stack, and pointing it stateside. (Or, in w3gm's case, putting a 3el up at 25', fixed west & splitting
/archives//html/Towertalk/2005-04/msg00125.html (8,665 bytes)

232. Re: [TowerTalk] simultaneous Horizontal and Vertical antennas (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 4 Apr 2005 12:55:12 -0400
Gary (TT): FM Stations transmit circular polarization, which results in signals being 3dB down in any single plane, but less susceptible to selective fading/interference problems, particularly with s
/archives//html/Towertalk/2005-04/msg00130.html (12,660 bytes)

233. Re: [TowerTalk] simultaneous Horizontal and Vertical antennas (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 4 Apr 2005 15:01:01 -0400
I'm inclined to think that multipath was at the root of the variations...in the sense that a varying series of angular arrivals swept across the response of the antenna. This is pretty normal. (I've
/archives//html/Towertalk/2005-04/msg00144.html (12,084 bytes)

234. [TowerTalk] (no subject) (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 5 Apr 2005 09:42:25 -0400
Tom's initial post..heavily snipped: I plan to clear an appropriate radius about the tower to permit antenna rotation only. Given this situation, would a freestanding tower be preferred over guyed? I
/archives//html/Towertalk/2005-04/msg00165.html (8,745 bytes)

235. [TowerTalk] Guying free-standing towers: the initial post (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 11 Apr 2005 08:54:39 -0400
If I remember correctly, this started with a question from a chap who is putting up a self-supporter which is too close to a power line. He asked if there were any problems with a safety guy. There w
/archives//html/Towertalk/2005-04/msg00355.html (7,973 bytes)

236. Re: [TowerTalk] Guying free-standing towers: the initial post (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 11 Apr 2005 10:14:57 -0400
Hi Tom, I see your point. Adding guys will distribute the compressive load over all 3 legs of the structure, rather than having it load only one. Even if the structure is pre-loaded with guy tension,
/archives//html/Towertalk/2005-04/msg00362.html (13,334 bytes)

237. [TowerTalk] guying (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 11 Apr 2005 11:35:18 -0400
I am reluctant to extend this thread...but there's a flaw here, imho. I'll make this my last on the topic: I beg to differ. The function of sensible guying is to prevent the tower from reaching its m
/archives//html/Towertalk/2005-04/msg00367.html (9,241 bytes)

238. [TowerTalk] HBX tower rotational loading (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 13 Apr 2005 13:28:19 -0400
I've been reluctant to continue this guying thread... but this really is slightly different...it's hbx/hbdx related: Yes Dave, *I* was one of those idiots who attempted using an HDBX48 tower to hold
/archives//html/Towertalk/2005-04/msg00428.html (8,740 bytes)

239. [TowerTalk] Base mounted rotor=great idea (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 13 Apr 2005 14:52:10 -0400
Multiple suggestions of this idea... Friend here had one with KLM KT34 on top. Antenna was rotated by long mast to rotator mounted at base. No torque from antenna was transmitted to tower. Worked fla
/archives//html/Towertalk/2005-04/msg00434.html (7,147 bytes)

240. [TowerTalk] hdbx48 failure (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 13 Apr 2005 17:33:56 -0400
Clearly, sheer winds from downbursts at leading edge of Tstorms can be catastrophic, and Chuck's tower was overloaded. BUT... If the guys had been connected using a triangular bracket, such as Rohn u
/archives//html/Towertalk/2005-04/msg00448.html (8,074 bytes)


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