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Total 175 documents matching your query.

61. RE: [TowerTalk] Re: Static, Lightning, and protection (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Wed, 24 Mar 2004 09:20:27 -0500
properly grounded towers and a significant reduction of strikes was very strong. To the extent that I worried about lightning damage until I got the big tower up and then I never had any more strikes
/archives//html/Towertalk/2004-03/msg00524.html (8,518 bytes)

62. Re: [TowerTalk] Modelling a basic stack (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 09 May 2004 22:51:20 -0400
before I get in too deep :~) Bert, I would first use YO7 to optimize the antennas in their free space stacked configuration. YO7 already has the A50-5S in the database so it is simply a matter of sel
/archives//html/Towertalk/2004-05/msg00169.html (8,690 bytes)

63. [TowerTalk] Modelling a basic stack (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 10 May 2004 07:20:37 -0400
submit to you that stacking two of a poor antenna is a twice-poor idea. And the A50-5S is a very poorly designed antenna. It is intended to be idiot-proof (which, I assume, is why all the elements ar
/archives//html/Towertalk/2004-05/msg00175.html (11,634 bytes)

64. [TowerTalk] Modelling a basic stack (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 10 May 2004 07:43:15 -0400
an HF stack, even if first optimized in free space at the planned stacking distance, would be de-optimized (is that a word?) once returned to the "above ground" environment, because the ground plane
/archives//html/Towertalk/2004-05/msg00177.html (9,056 bytes)

65. [TowerTalk] YOed older 4 el 20 meter CC Skywalkers (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 10 May 2004 07:58:08 -0400
I presently have three 4 element 20 meter Skywalkers assembled and waiting to go up and I was wondering if anyone has optimized these antennas? They will be stacked 32/62/102. John, I would be suspec
/archives//html/Towertalk/2004-05/msg00179.html (7,995 bytes)

66. Re: [TowerTalk] Modelling Stacks (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 10 May 2004 19:10:03 -0400
YO7. I am stacking 2 4L SteppIR antennas which allows me to change element lengths but the element spacing is fixed. In attempting to optimize I get different spacing. I would prefer not to change sp
/archives//html/Towertalk/2004-05/msg00197.html (7,858 bytes)

67. Re: [TowerTalk] YOed older 4 el 20 meter CC Skywalkers (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Tue, 11 May 2004 07:28:08 -0400
At 06:46 PM 5/10/04, Trentkd5ia@aol.com wrote: I'm confused. When I model my future tower using YT, the best performance (pattern and gain) occurs with a spacing of 0.5 wavelength. This spacing outpe
/archives//html/Towertalk/2004-05/msg00201.html (9,868 bytes)

68. [TowerTalk] Bytemark (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Thu, 13 May 2004 07:00:38 -0400
I have and got excellent service late last year. I don't recall the name was anything but Bytemark then but the web page reference I used still works. If you look at the following page, it appears CW
/archives//html/Towertalk/2004-05/msg00274.html (7,017 bytes)

69. Re: [TowerTalk] Substitute for YO? (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sat, 05 Jun 2004 07:36:07 -0400
for DOS? Simple and reliable would the the main criterias. I assume you know that YO (at least the YO7 I have) will operate in the "DOS under Windows mode", unlike CTDOS which requires a full DOS boo
/archives//html/Towertalk/2004-06/msg00060.html (7,778 bytes)

70. [TowerTalk] Radio Shack 300 Ohm Line Characteristics (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 13 Jun 2004 09:38:13 -0400
I'm planning to try an 80m dipole fed with Radio Shack 300 ohm twin-lead for Field Day. I only plan to run QRP so power handling is not a consideration. In using the method on p.34 of April 2004 QST,
/archives//html/Towertalk/2004-06/msg00272.html (8,287 bytes)

71. Re: [TowerTalk] Radio Shack 300 Ohm Line Characteristics (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 13 Jun 2004 14:16:19 -0400
At 01:16 PM 6/13/04, you wrote: Belden lists 22 AWG 300 ohm line as 1.4dB/100 ft at 100Mhz while stepping up to 20 gauge reduces loss to 1.1dB/100ft @ 100MHz. That's the only data I have here in my c
/archives//html/Towertalk/2004-06/msg00277.html (9,533 bytes)

72. [Antennaware] Velocity factor of insulated #14 stranded wire (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 20 Jun 2004 19:00:30 -0400
I know the new version of Eznec 4.0 handles this but does anyone know the correction factor for insulated it is about 95% but does anyone know for sure? 73, Bill W4ZV ________________________________
/archives//html/Towertalk/2004-06/msg00437.html (6,786 bytes)

73. [TowerTalk] Follow Up - Velocity factor of insulated #14 strandedwire (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 21 Jun 2004 22:13:07 -0400
Thanks for many responses! They were in unanimous agreement that the resonant frequency is raised by about 3% for insulated versus bare wire. 73, Bill W4ZV ___________________________________________
/archives//html/Towertalk/2004-06/msg00449.html (7,109 bytes)

74. Re: [TowerTalk] Stacking Distance for M2'd 6m7JHV? (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Tue, 13 Jul 2004 07:13:33 -0400
W5WVO wrote:>But how to model the effect of various phase shifts on take-off angle? Does anyone have a handle on that? I don't know of any software that is set up to do the math involved in this scen
/archives//html/Towertalk/2004-07/msg00399.html (10,575 bytes)

75. Re: [TowerTalk] Stacking Distance for M2'd 6m7JHV? (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Tue, 13 Jul 2004 07:38:37 -0400
When I opened HFTA to look at the pdf file, it just so happened the last plot I had done with HFTA included the 180 degree phase option, so it was easy to put it on a webpage. Dark blue is a 3-stack
/archives//html/Towertalk/2004-07/msg00401.html (9,142 bytes)

76. [TowerTalk] Homebrew Tower (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Wed, 25 Aug 2004 14:03:06 -0400
Yes. Here's a homebrew tower I climbed at HC8N: http://users.vnet.net/btippett/new_page_7.htm (2nd photo down) "By the way, the homemade tower was constructed like Rohn 45 but using rebar for the Z-b
/archives//html/Towertalk/2004-08/msg00544.html (7,546 bytes)

77. Re: [TowerTalk] antennas in trees (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 20 Sep 2004 09:41:58 -0400
Gotham vertical. That was about the poorest antenna commercially manufactured, so the only good thing they could say about it was how much DX people worked when using one. Tom, you may be mixing fact
/archives//html/Towertalk/2004-09/msg00425.html (9,198 bytes)

78. Re: [TowerTalk] Vertcal Dipole (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 17 Oct 2004 16:10:30 -0400
meters) where it is end fed with coax. Yes but why not use a simple LC matching circuit? The following circuits work best with a single 1/4 wl radial counterpoise in addition to the 1/2 wl radiator:
/archives//html/Towertalk/2004-10/msg00461.html (9,967 bytes)

79. Re: [TowerTalk] Take off angles, VOACAP, etc (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 17 Oct 2004 16:31:41 -0400
you work the next layer of signals in a contest. High angles predominate in the latter 2/3's of most openings I've seen on 10 meters. The lower angles of my 3-stack typically becomes too low after th
/archives//html/Towertalk/2004-10/msg00463.html (7,510 bytes)

80. Re: [TowerTalk] Vertcal Dipole (score: 1)
Author: Bill Tippett <btippett@alum.mit.edu>
Date: Sun, 17 Oct 2004 21:27:52 -0400
you get away with it is you are running QRP, or have a lucky feedline length. Par's monoband End Fedz are rated at "a conservative 100W" although the distributor (Universal Radio) says "a conservativ
/archives//html/Towertalk/2004-10/msg00470.html (11,268 bytes)


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