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1. Topband: Skewed Propagation Paths (score: 1)
Author: (Dave Bowker)
Date: Thu, 16 Jan 2003 16:23:48 -0500
Tom, I don't claim to be an expert in 160M propagation, but I DO question = your statement ["medium frequency signal propagation path skewing is that the transmitted RF signal will "always" seek to =
/archives//html/Topband/2003-01/msg00094.html (7,242 bytes)

2. Topband: A few words (score: 1)
Author: (Dave Bowker)
Date: Sun, 19 Jan 2003 08:06:54 -0500
There have been several articles published in CQ related to this thread = which may be of interest. "The 160 Meter Band, An Enigma Shrouded in a Mystery - Parts I and II", = CQ Mar/Apr 1998. "Skewed
/archives//html/Topband/2003-01/msg00148.html (7,163 bytes)

3. Topband: chicken wire ground screen (score: 1)
Author: (Dave Bowker)
Date: Sun, 1 Sep 2002 07:18:18 -0400
There is another "negative" aspect to using mesh, chicken wire, welded fencing, etc., in the ground system of verticals, and that is the losses these screens incur due to eddy currents created by the
/archives//html/Topband/2002-09/msg00006.html (7,723 bytes)

4. Topband: chicken wire ground screen (reply) (score: 1)
Author: (Dave Bowker)
Date: Sun, 1 Sep 2002 19:22:50 -0400
Gary, K9AY is quite correct in his response that [copper] mesh used as an artificial ground at HF and VHF has proven quite effective and that radar and satellite antennas use perforated reflectors to
/archives//html/Topband/2002-09/msg00012.html (9,076 bytes)

5. Topband: chicken wire ground screen (reply to W4EF comments] (score: 1)
Author: (Dave Bowker)
Date: Mon, 2 Sep 2002 14:32:26 -0400
In Response to W4EF's and other (private email) comments: There are three different [primary] currents in effect beneath and around a vertical radiator operating over earth and above an artificial gr
/archives//html/Topband/2002-09/msg00016.html (9,269 bytes)

6. Topband: Displacement currents (score: 1)
Author: (Dave Bowker)
Date: Wed, 4 Sep 2002 15:13:20 -0400
Tom, I think there may be a slight misunderstanding here. Displacement currents DO NOT flow through the ground, but currents which are considered to be flowing from the element, through the air diele
/archives//html/Topband/2002-09/msg00035.html (7,516 bytes)

7. Topband: DU9/N0NM Today (score: 1)
Author: (Dave Bowker)
Date: Sat, 28 Sep 2002 07:15:31 -0400
Heard one short burst from Jon at 1005, and another at 1030 today. Conditions here were extremely quiet today. BTW: my short path to Jon is right through the polar auroral zone, with the short path i
/archives//html/Topband/2002-09/msg00204.html (6,743 bytes)

8. Topband: Internet access via power lines reborn in Europe (score: 1)
Author: (Dave Bowker)
Date: Sun, 2 Sep 2001 09:01:23 -0400
Can you imagine the converse interference problem caused by AM BC, hams, and RF from all sorts of emitters getting into the power distribution lines and raising havock with these internet modems? 73,
/archives//html/Topband/2001-09/msg00007.html (7,570 bytes)

9. [Topband: Lightning Arrestor] (score: 1)
Author: (Dave Bowker)
Date: Sun, 13 May 2001 12:39:18 -0400
I don't recommend use of power-frequency lightning arrestors (LA's) in RF applications for the following reasons: 1. A 5kV LA functions at 10-20 times the required sustaining voltage necessary for a
/archives//html/Topband/2001-05/msg00025.html (10,156 bytes)

10. Topband: 1.700 - 1.800 mhz (score: 1)
Author: (Dave Bowker)
Date: Mon, 5 Feb 2001 07:26:25 -0500
The FCC's on-line frequency allocaton table is available at: . It is a large .pdf document of 186 pages, covering the entire ITU spectrum. The ITU "
/archives//html/Topband/2001-02/msg00023.html (7,181 bytes)

11. Topband: The Sun Does a Flip (score: 1)
Author: (Dave Bowker)
Date: Fri, 16 Feb 2001 10:45:45 -0500
I thought TopBanders would be interested in this. "NASA scientists who monitor the Sun say that our star's awesome magnetic field is flipping -- a sure sign that solar maximum is here. http://science
/archives//html/Topband/2001-02/msg00075.html (6,780 bytes)

12. Topband: FR/F6KDF/T Update (score: 1)
Author: (Dave Bowker)
Date: Tue, 8 Aug 2000 06:42:34 -0400
Here are a few excerpts from Eric, F5SIH relating to TopBand...updates of all activities are available at: 73, Dave, K1FK Fort Kent, ME ~~~~~~~~~~~~ AUGUST 6th
/archives//html/Topband/2000-08/msg00021.html (7,167 bytes)

13. Topband: FR/F6FDX/T Situation (score: 1)
Author: (Dave Bowker)
Date: Fri, 11 Aug 2000 20:12:48 -0400
For what it's worth to TopBanders (as reported by Eric, F5SIH) 73, Dave, K1FK Fort Kent, ME ~~~~~~~~~~~~ AUGUST 10th 2000 The weather conditions got very bad in last 48 hours. Very high wind and heav
/archives//html/Topband/2000-08/msg00037.html (7,265 bytes)

14. Topband: Interesting Propagation - 7P8AA (score: 1)
Author: (Dave Bowker)
Date: Thu, 20 Jul 2000 11:03:42 -0400
7P8AA was booming into northern Maine around 0050Z - 0115Z last evening, with his signal holding at solid 589 - 599 on the 1/4-wave vertical for a good 20+ minutes. Amazingly, he was not hearing the
/archives//html/Topband/2000-07/msg00036.html (7,202 bytes)

15. Topband: Broadcast Station: Harmonic Supression? (score: 1)
Author: (Dave Bowker)
Date: Mon, 27 Dec 1999 08:26:18 -0500
It is the braoacast transmitter manufacturer's and end-user's joint responsibility to correct any actual interference problems to either other BC services or NON-BROADCAST communications systems (thi
/archives//html/Topband/1999-12/msg00293.html (8,050 bytes)

16. Topband: Item of Interest to Top Banders (score: 1)
Author: (Dave Bowker)
Date: Sun, 31 Oct 1999 06:27:12 -0500
The ARRL Web Extra for October 29, 1999 has an item entitled "Will the Real HF Buzz Saw Please Stand Up?" that may be of interest to Top Band
/archives//html/Topband/1999-10/msg00192.html (7,054 bytes)

17. Topband: HZ1AB Planned Top Band Activity (score: 1)
Author: (Dave Bowker)
Date: Tue, 14 Sep 1999 19:36:07 -0400
Thomas, SM0CXU, informs me that he will be active from HZ1AB during the Scandinavian Activity Contest (SAC)-CW from approximately 1700Z 18 Sep to 19 Sep. Since 160M is NOT a contest band for (SAC)-CW
/archives//html/Topband/1999-09/msg00066.html (7,153 bytes)

18. RE: Topband: Antenna Bridge (score: 1)
Author: "Dave Bowker" <>
Date: Tue, 4 Nov 2003 18:23:15 -0500
A complete description of the GR-916 Bridge, transformers, and the standard resistor was described by D.B. Sinclair in the Proceedings of the Institute of Radio Engineers, November, 1940, pp 497-503.
/archives//html/Topband/2003-11/msg00016.html (6,879 bytes)

19. RE: Topband: Antennas, Guy Ropes, and High Winds (score: 1)
Author: "Dave Bowker" <>
Date: Sun, 7 Mar 2004 14:50:29 -0500
See my upcoming article "K1FK 75' Vertical for 80 & 160 Meters" (tenatively scheduled to be published in the June 2004 issue of QST), on how to construct, erect, and place such an animal into operat
/archives//html/Topband/2004-03/msg00073.html (8,024 bytes)

20. Re: Topband: feeding a top loaded vertical (score: 1)
Author: "Dave Bowker" <>
Date: Mon, 10 Oct 2005 17:44:47 -0400
Jelmer, See my article on a 75' vertical for 80/160 in June 2004 QST in which I use L-networks for feedpoint matching ... very simple and far less complex than any Gamma matching schemes. Also see Ju
/archives//html/Topband/2005-10/msg00056.html (6,708 bytes)

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