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Total 284 documents matching your query.

221. Re: [TowerTalk] cage dipole (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Fri, 10 Apr 2009 06:37:49 -0400
Horsehockey! A cage dipole is simply lower Q and therefore will exhibit wider bandwidth than a single wire dipole. It will exhibit NO gain over a single wire dipole, installed at the same height, ove
/archives//html/Towertalk/2009-04/msg00313.html (7,988 bytes)

222. Re: [TowerTalk] polarization change (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Fri, 10 Apr 2009 11:08:06 -0400
I wasn't going to comment on this, because wiser heads have prevailed, on this topic, for the most part. HOWEVER, I learned something today that may be worth contributing to the discussion: I have al
/archives//html/Towertalk/2009-04/msg00323.html (8,274 bytes)

223. Re: [TowerTalk] pre-Dayton season (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sun, 19 Apr 2009 16:49:21 -0400
Every year, about this time, we seem to fixate on a topic and beat it within inches of its life. We're pretty much done with contest season. It isn't warm enough for a lot of antenna work, yet. And V
/archives//html/Towertalk/2009-04/msg00539.html (7,101 bytes)

224. Re: [TowerTalk] sloping dipole arrays (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Mon, 20 Apr 2009 15:52:16 -0400
I have seen K1WA's excellent article in the Antenna Handbook for years regarding sloping half-wave dipole arrays. His design switches both the center conductor and braid for each feedline. Is it real
/archives//html/Towertalk/2009-04/msg00553.html (7,314 bytes)

225. Re: [TowerTalk] sloping dipole arrays (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Mon, 20 Apr 2009 17:53:08 -0400
Steve's question about switching dipoles in a sloper array raises the OTHER question... who makes a switch which can readily be modified to satisfy the requirements of this switching? i.e. isolating
/archives//html/Towertalk/2009-04/msg00563.html (7,135 bytes)

226. Re: [TowerTalk] plastic owl (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Wed, 22 Apr 2009 14:34:26 -0400
Mike, AD6AA pointed out the use of CD's as deterents to bird populations camping on antennas. CD's hung from light line have been used successfully on the foredeck of sailboats, to scare off gulls an
/archives//html/Towertalk/2009-04/msg00647.html (7,619 bytes)

227. [TowerTalk] loops (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Fri, 24 Apr 2009 15:55:07 -0400
W1KSZ asked about crossed k9ay loops...and whether having 3 loops would work, giving more azimuthal resolution. -0- I had a pair of k9ay loops, in Maryland, and was not happy with the results. Princi
/archives//html/Towertalk/2009-04/msg00708.html (7,414 bytes)

228. Re: [TowerTalk] AB577 (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sun, 26 Apr 2009 20:51:04 -0400
First, for a temporary installation, I would be somewhat leery of taking that mast to 75'. It has spaghetti-like properties when extended that high. You can do it... but why? Perhaps you should back
/archives//html/Towertalk/2009-04/msg00748.html (6,886 bytes)

229. Re: [TowerTalk] tree antenna (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Mon, 27 Apr 2009 08:01:24 -0400
Let's see... that was the April edition of what year? n2ea _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting
/archives//html/Towertalk/2009-04/msg00760.html (6,960 bytes)

230. Re: [TowerTalk] source for tower bolts (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Tue, 28 Apr 2009 09:26:42 -0400
K1LI is looking for bolts for his Rohn guy attachment brackets. Original galvanized bolts apparently are unavailable from any industrial sources. My Question is this: What's wrong with using stainles
/archives//html/Towertalk/2009-04/msg00796.html (7,677 bytes)

231. Re: [TowerTalk] pl259 (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Tue, 05 May 2009 09:21:34 -0400
We had a technique for rg58/59 used for video cabling which differs from the standard. It was used at RCA network, and the CE at the instructional TV studio where I worked as a student, had come from
/archives//html/Towertalk/2009-05/msg00065.html (7,308 bytes)

232. Re: [TowerTalk] Bill in the House (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Wed, 06 May 2009 15:54:13 -0400
The topic, while political, IS relevant here. And, as someone observed, since disasters tend to be local, the resulting legislation could work against regulations permitting useful structures for int
/archives//html/Towertalk/2009-05/msg00105.html (8,598 bytes)

233. Re: [TowerTalk] identify this antenna (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Thu, 07 May 2009 16:12:32 -0400
Bob, Looks to be a vertical collinear, or "franklin" array. Probable frequency determined by the radials = .25 lambda, at the lowest freq. The ID by w9az, jim, may indeed be correct. However, with t
/archives//html/Towertalk/2009-05/msg00135.html (7,738 bytes)

234. Re: [TowerTalk] log periodic vs. small steppir (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Fri, 08 May 2009 15:22:40 -0400
I made my initial comments off-reflector, but this seems to be drifting, so will summarize here. I went from a kt34A to a T8 to a 3 el SteppIR, so can comment directly. 1) The gain of the T6 is NOT m
/archives//html/Towertalk/2009-05/msg00166.html (8,828 bytes)

235. Re: [TowerTalk] rohn 25g foldover (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sat, 09 May 2009 20:24:05 -0400
Richard, I doubt seriously that you could put anything useful on it, and not guy it. On the other hand, I have first hand experience with 45G unguyed, to 60', using a foldover section. It was support
/archives//html/Towertalk/2009-05/msg00197.html (7,414 bytes)

236. Re: [TowerTalk] cebik & antennas (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sun, 10 May 2009 15:31:43 -0400
note: this link has evidently changed since W7SG was last on it. Jack Stone is protecting the copyright to LB's articles. going to the link does not yield a choice "tales and technicals", although it
/archives//html/Towertalk/2009-05/msg00213.html (7,019 bytes)

237. Re: [TowerTalk] Cebik (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sun, 10 May 2009 16:36:06 -0400
Ken, First, my thanks for reminding me that I am sometimes over-quick to react to things. Secondly, and more importantly, for causing me to re-connect with LB's writings. Many of the discussion topic
/archives//html/Towertalk/2009-05/msg00216.html (9,752 bytes)

238. [TowerTalk] G 1000 DXA alignment? (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sun, 31 May 2009 15:22:15 -0400
Anybody got a foolproof alignment procedure for a Yaesu g1000dxa rotor? I replaced the motor in this thing, like 7 years ago, and it's been on the shelf ever since. Have now confirmed that it rotates
/archives//html/Towertalk/2009-05/msg00532.html (7,784 bytes)

239. Re: [TowerTalk] g 1000dxa alignment (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Sun, 31 May 2009 21:44:54 -0400
Thanks, all for the input. In particular Dennis and Hans, for the firsthand experience. So far, I've determined that you have to align it, pointing North, (got my compass and plastic owl, right here.
/archives//html/Towertalk/2009-05/msg00536.html (7,558 bytes)

240. Re: [TowerTalk] optimum vertical length (score: 1)
Author: jim Jarvis <jimjarvis@optonline.net>
Date: Mon, 01 Jun 2009 07:53:05 -0400
Jim, 43' was chosen as a length because it represents 5/8 wave on 20m, which is the point at which a higher angle lobe starts emerging, but groundwave is maximized. Clearly, the antenna is the bigges
/archives//html/Towertalk/2009-06/msg00002.html (7,331 bytes)


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