Mail Archive Search: <+from:tom.mcdermott4@yahoo.com>

Results:

References: [ +from:tom.mcdermott4@yahoo.com: 7 ]

Total 7 documents matching your query.

1. Re: [TowerTalk] Waterproof enclosures at base of tower (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Fri, 18 Jan 2008 08:15:12 -0800 (PST); It depends on the application, I built a box to hold matching network for a 80m/160m shunt-fed vertical. At 1500w, the voltage on the series matching capacitor and the feedthrough insulator to the g; /archives//html/Towertalk/2008-01/msg00360.html (8,913 bytes)
2. Re: [TowerTalk] About to pull the trigger (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Fri, 25 Jan 2008 04:43:43 -0800 (PST); Built almost this same setup in 1984 using Rohn 45 (different rotators). Comments: 2. I don't know if there have been mechanical improvements in the 4M40 since 1984. Referencing the older design: th; /archives//html/Towertalk/2008-01/msg00507.html (10,848 bytes)
3. Re: [TowerTalk] Wireman Balun kits (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Thu, 6 Mar 2008 07:36:20 -0800 (PST); There are several possible failure modes for baluns. Besides those involving the magnetic core material, high SWR can lead to excessive voltage between the windings. Tom, W8JI has written about that; /archives//html/Towertalk/2008-03/msg00073.html (7,476 bytes)
4. Re: [TowerTalk] 3El Bobtail for 80 meters (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Sun, 6 Jul 2008 11:46:58 -0700 (PDT); There would be two configurations for a 9 element Bobtail curtain: One would be to just keep extending the Bobtail array, one wire on the top that is 4 wavelengths long instead of 1, and instead; /archives//html/Towertalk/2008-07/msg00145.html (8,986 bytes)
5. Re: [TowerTalk] Elevated Radials (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Fri, 5 Sep 2008 06:54:04 -0700 (PDT); Hi Bob: In general, elevated radials are strongly resonant, and need to be treated like a radiating part of the antenna (because they are). This means making sure that current is shared equally bet; /archives//html/Towertalk/2008-09/msg00056.html (7,623 bytes)
6. Re: [TowerTalk] Antenna software (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Sat, 6 Sep 2008 14:21:12 -0700 (PDT); Here's another vote for 4NEC2. Particularly helpful is the 3D visualization of the pattern in multi-colors. Everyone I show a pattern to on-screen instant understands the antenna pattern when they s; /archives//html/Towertalk/2008-09/msg00086.html (8,466 bytes)
7. Re: [TowerTalk] tower resonances (score: 1): Author: Tom McDermott <tom.mcdermott4@yahoo.com>; Date: Thu, 12 Feb 2009 09:13:37 -0800 (PST); Forrest Gehrke K2BT wrote a 6-part series in Ham Radio in 1983 / 1984 on phased vertical antennas. He came up with a technique to derive the Z-parameter matrix (self and mutual impedances 2-po; /archives//html/Towertalk/2009-02/msg00292.html (10,479 bytes)

Current List: 1 - 7
Page: [1]