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101. [TowerTalk] collapsing steppIR elements (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Fri, 7 May 2004 16:19:24 -0000
Interesting idea, to attach the tape to the tips of the nesting fiberglass tubes. Couple of problems with that, though. First, it wouldn't be as well weather sealed. Second, although the telescoping
/archives//html/Towertalk/2004-05/msg00136.html (7,201 bytes)

102. [TowerTalk] URI magic antennas (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 8 Jun 2004 01:41:54 -0000
My daughter graduated from URI. I've got the $60k poloshirt to prove it. The press release says nothing, except to suggest 3 dB greater signal from whatever this loaded monopole is, vs. 'normal' mono
/archives//html/Towertalk/2004-06/msg00136.html (6,966 bytes)

103. [TowerTalk] antenna magic (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 8 Jun 2004 14:22:43 -0000
Quoth the press release: "The distributed- load, monopole antennas are smaller, produce high efficiency, and retain good to excellent bandwidth. And they have multiple applications." Most of the appl
/archives//html/Towertalk/2004-06/msg00154.html (7,379 bytes)

104. [TowerTalk] Speculation (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 8 Jun 2004 18:14:05 -0000
Always an entertainment to watch the high-gain, High-Q ringing on this site. Often teases out good stuff. Having spoken with the author, I'm still waiting for the 'inventor' to call my office. Althou
/archives//html/Towertalk/2004-06/msg00168.html (8,654 bytes)

105. [TowerTalk] RE: as I said.... (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 8 Jun 2004 22:01:45 -0000
you're most likely correct, Joe. There are a lot of ways to conceal antennas....none of which are efficient. There are a few ways to make an efficient, small antenna...but with a high-Q result, makin
/archives//html/Towertalk/2004-06/msg00179.html (8,209 bytes)

106. [TowerTalk] ma550/ antenna height (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 16 Jun 2004 16:37:15 -0000
Folks, I had my 3 el SteppIR at various heights, in VT, on a military pushup mast. 30, 50, 65, 80, 100'. It wasn't dynamically adjustable, and it was now two seasons ago, so there was more sun to pla
/archives//html/Towertalk/2004-06/msg00366.html (7,673 bytes)

107. [TowerTalk] LPDA's & stepper tuned yagis vs. trapped tribanders &multiple single banders on one boom (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 23 Jun 2004 02:43:53 -0000
Complex subject...and one which is fraught with .... opinion. there's also data, but why let that get in the way? Here's my observation: 1) Tennadyne T8 was a great antenna. Outperformed any trapped
/archives//html/Towertalk/2004-06/msg00485.html (9,143 bytes)

108. [TowerTalk] beam antenna patterns; groundwave (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Jun 2004 17:48:42 -0000
Folks, While I agree with Tom, in theory, that all manner of localized effects can come into play, mapping pattern using groundwave at far-field has SOME value. I did it routinely in Vermont, with a
/archives//html/Towertalk/2004-06/msg00588.html (7,567 bytes)

109. RE: [TowerTalk] beam antenna patterns; groundwave (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 26 Jun 2004 20:13:21 -0000
How, pray tell, did you calculate 6 db f/b on a VERTICAL? ... Did you rotate it? Any WHY? Don N8DE Yup. I should have explained. The R7000 was mounted on the mast, about 3' above the yagi or lpda. I
/archives//html/Towertalk/2004-06/msg00590.html (10,353 bytes)

110. [TowerTalk] yagi/lpda field tests (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 27 Jun 2004 18:02:54 -0000
If a test field were set up such that the monitor antenna and device-under-test were 10 wavelengths apart, and such that there were 10 wavelengths free space around each antenna in all directions (ex
/archives//html/Towertalk/2004-06/msg00600.html (8,309 bytes)

111. [TowerTalk] antenna FS measurements (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 29 Jun 2004 15:19:56 -0000
W/resp to antenna pattern measurement techniques, some very important things have been posted here, in fragmented form, from several knowledgeable guys: * You can measure at 0 degrees azimuth, using
/archives//html/Towertalk/2004-06/msg00668.html (9,082 bytes)

112. RE: [TowerTalk] antenna FS measurements (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 30 Jun 2004 01:33:58 -0000
I'd suspect the short term stability of the MJF attenuators is reasonably good. Most things ARE, for short intervals. The big source of error is likely switches in the attenuator. I agree with Tom, h
/archives//html/Towertalk/2004-06/msg00694.html (13,263 bytes)

113. [TowerTalk] slipping every so slightly off-topic (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 30 Jun 2004 16:39:06 -0000
Tom, TT: While I agree generally that receivers tend to be non-linear, and their AGC response curves tend to be non-logarithmic, as well.... I'm going to pick a small bone. -0- You incorrectly lump t
/archives//html/Towertalk/2004-06/msg00709.html (9,822 bytes)

114. [TowerTalk] G1000dxa (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 30 Jun 2004 18:50:37 -0000
I used a G1000dxa rotor for several years with a LPDA, then applied it to turning a base-rotatable, 90' AB621 pole with the T8 lpda and 2 el 40 beam on it. Worked fine, until the guyrings iced up, an
/archives//html/Towertalk/2004-06/msg00719.html (7,077 bytes)

115. [TowerTalk] managing multi-station interference (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 5 Jul 2004 14:02:34 -0000
This was an interesting thread...but the problem has been 'solved', to the extent that it CAN be solved, by multi-multi stations in competition. I believe W2VJN, George, at INRAD, has assembled a boo
/archives//html/Towertalk/2004-07/msg00133.html (9,526 bytes)

116. [TowerTalk] narrowband filters (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 5 Jul 2004 19:21:46 -0000
Jim, Jim, Tom, Mike, et. al.: I don't recall where this thread started, but I think it was someone looking for magic filters for in-band FD applications. However, if you start with all monoband anten
/archives//html/Towertalk/2004-07/msg00163.html (8,587 bytes)

117. [TowerTalk] Why would you 'repair' a section of 25G? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Fri, 9 Jul 2004 01:26:43 -0000
I must admit, I came in late to this thread... but why would anyone contemplate repairing a section of rohn 25G, when you can buy replacement for 100 bucks? Or, if you can find it used, for 30-50? Be
/archives//html/Towertalk/2004-07/msg00320.html (7,784 bytes)

118. [TowerTalk] exothermic replies (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 17 Jul 2004 17:57:16 -0000
Um....I hate to be a PITA, but could we avoid listing every bloody message to which we're replying? It's tedious as hell to have to wade through a sea of all with stuff we've read before, just to see
/archives//html/Towertalk/2004-07/msg00480.html (7,371 bytes)

119. [TowerTalk] Tower sections vs. mast? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 22 Jul 2004 01:28:48 -0000
Been there & done this calculation. 45G is cheaper than good mast, and possibly lighter. Certainly, ligher mast of equivalent strength costs more than 45g sections. Have had 60' of 46G with 20' of ma
/archives//html/Towertalk/2004-07/msg00590.html (7,581 bytes)

120. [TowerTalk] Towerheight (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 22 Jul 2004 03:48:17 -0000
I obviously missed the central point of this post, and responded to mast vs. tower cost/weight discussion. There MAY be a subtlety in the ordinance language, regarding 'antenna support' or 'tower' as
/archives//html/Towertalk/2004-07/msg00598.html (7,689 bytes)


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