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1. Topband: Vertical antenna near field efficiency (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Thu, 19 Apr 2001 14:35:46 -0400; Most of the time there seems to be a focus among us upon the angle of radiation, the effects of the ground immediately under the radial structure, and the resulting lack of low-angle radiation when f; /archives//html/Topband/2001-04/msg00047.html (8,626 bytes)
2. Topband: Beverages and useful wave angles (score: 1): Author: jbmitch@vt.edu (John B. Mitchell); Date: Sat, 10 Jun 2000 15:32:24 -0400; Hi Herb, Yes, I can attest to the fact that poor ground seems to really help beverage performance. Here, in SWVA, the Appalachians are mostly limestone, karst regions, with a thin overlay of mostly d; /archives//html/Topband/2000-06/msg00020.html (9,942 bytes)
3. TopBand: Grid Square Look up site? (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Sun, 27 Dec 1998 12:37:10 -0500; Apologies if this was covered before here, but does anyone have info on an internet site that will give grid squares for international cities? A couple people called in during SP from Carib and SA wh; /archives//html/Topband/1998-12/msg00275.html (7,584 bytes)
4. TopBand: Grid Square Look up site? (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Sun, 27 Dec 1998 20:31:29 -0500; What would Stew Perry decide? Isn't the important thing working the DX? Or is it ensuring everyone knows this obscure bit of data relating to their location? Besides if you call CQ TEST and they repl; /archives//html/Topband/1998-12/msg00285.html (10,442 bytes)
5. TopBand: Grid Square Look up site? (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Mon, 28 Dec 1998 00:04:55 -0500; I'd like to know what the consensus of the contest committee is. It only makes a few points difference in my modest log anyway, so what's the verdict? Can someone who enters the contest casually, and; /archives//html/Topband/1998-12/msg00289.html (9,504 bytes)
6. TopBand: Re: Counties on 160M (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Fri, 06 Nov 1998 02:34:36 -0500; Hi Leif, and all, At the risk of taking bandwidth (I haven't posted here in months, so perhaps I may be granted some latitude), might I suggest another possibility, one that I believe is reachable. (; /archives//html/Topband/1998-11/msg00030.html (8,393 bytes)
7. TopBand: CW segment (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Tue, 07 Apr 1998 14:05:25 -0400; I don't know, but I'll try to find out. Interestingly, this subject (a CW-only allocation for 160) was brought up for discussion at the time at one of the large contest club meetings, and the majorit; /archives//html/Topband/1998-04/msg00070.html (8,323 bytes)
8. TopBand: VP8/G4VFU (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Sat, 25 Apr 1998 11:08:46 -0400; Alex, If it's any comfort to you, I was in that SSB pileup, and was one of only three NA stations to get through, after many repeats, which was just pure lucky conditions. He just wasn't hearing the; /archives//html/Topband/1998-04/msg00240.html (9,239 bytes)
9. TopBand: Elevated radials (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Fri, 06 Mar 1998 15:00:17 -0500; Hi Larry, et al, I would imagine the same skin effect is responsible for the depth of radial current flow in soil as it is for current in the antenna near field and fresnel zone, i.e., the lower the; /archives//html/Topband/1998-03/msg00107.html (10,535 bytes)
10. TopBand: Elevated Radials (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Wed, 18 Mar 1998 22:41:37 -0500; As an exercise, thought I'd try to write how this seems to me. From what I've read and experimented about the subject, which is not nearly as much as many here, there seem to be (at least) several va; /archives//html/Topband/1998-03/msg00282.html (12,581 bytes)
11. TopBand: Elevated Radials (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Fri, 20 Mar 1998 01:56:04 -0500; Hi Tom, thanx for the well-considered reply. Oops, I wasn't clear enough. I was referring to a reference 1/4 wave radiator. The point was that folding over portions of it to make an Inverted L, which; /archives//html/Topband/1998-03/msg00319.html (15,482 bytes)
12. TopBand: Elev. Radial Qx. (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Sun, 22 Mar 1998 02:05:13 -0500; I am still very interested to hear from anyone about this diagram I posted several days ago. No one seems to have an opinion. The question is: what further improvement is realized by using more than; /archives//html/Topband/1998-03/msg00389.html (7,536 bytes)
13. TopBand: Re: Elev. Radial Qx. (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Sun, 22 Mar 1998 16:44:00 -0500; Thanx very much Earl, for running this. Looks like a lot of work for a quarter of a db, to me ; ) This establishes a base constant for plannng elevated radial systems, imo. Now that I know there is a; /archives//html/Topband/1998-03/msg00406.html (8,258 bytes)
14. TopBand: Elevated Radials (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Mon, 23 Mar 1998 18:45:01 -0500; In fact, if you really have perfect ground, zero radials Well, no it isn't. Referring to 'SE's EZNEC results, there was about 1db gained from elevating the feedpoint and whatever radial system above; /archives//html/Topband/1998-03/msg00432.html (9,611 bytes)
15. TopBand: Elevated Radials (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Mon, 23 Mar 1998 22:51:00 -0500; HI, this is beginning to seem like ping pong to me, too. I'm not sure what good it will do to hash this out again, but I thought SE's results were quite clear in showing that elevated feed point over; /archives//html/Topband/1998-03/msg00438.html (9,646 bytes)
16. TopBand: Common mode rejection filters (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Wed, 04 Feb 1998 18:53:15 -0500; topic is of interest and importance to Top-banders. Thanks, Bob, for breaking the ice on this one. I couldn't agree more. This reflector has become quite sterile of late, and I've considered dropping; /archives//html/Topband/1998-02/msg00041.html (8,101 bytes)
17. TopBand: Four-square antennas/ interaction effects (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Fri, 02 Jan 1998 03:49:05 -0500; In brainstorming some new antennas, an issue arises. With a four square made up of 4 inverted L's, suspended from orthogonal catenaries off a tower, what effect, if any will the central supporting to; /archives//html/Topband/1998-01/msg00013.html (8,015 bytes)
18. TopBand: Summary: four-square interactions (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Sat, 03 Jan 1998 15:36:40 -0500; Thanks to all for the information. Below are the replies received. They supply just what I need to carry out further research. Many thanks! 73, John K4IQ -- I'm using something similar to what you're; /archives//html/Topband/1998-01/msg00035.html (11,817 bytes)
19. TopBand: HELP with Beverage Switching ? (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Thu, 15 Jan 1998 00:12:54 -0500; Hi John, I use an MFJ six position switch (Mdl 1701, the cheapie!) and coax/pl259 feeds to bevs. No problems with isolation. The MFJ seems to have a robust mechanical construction, so I don't worry a; /archives//html/Topband/1998-01/msg00129.html (7,171 bytes)
20. [Fwd: Re: TopBand: qso ??] (score: 1): Author: jbmitch@vt.edu (John Mitchell); Date: Fri, 05 Dec 1997 00:29:29 -0500; I try to avoid jumping into most of these "controversy" threads on this reflector, but feel I must support Tom on this one. I think his point is that to ask for assistance from the reflector communit; /archives//html/Topband/1997-12/msg00086.html (8,844 bytes)

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