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21. Topband: beverages (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 22 May 2004 17:50:33 -0000
It's been a while since I read Beverage's article on wave antennas, but I, too, recall a discussion of diversity reception on beverages which were multiple wavelengths long. Incidentally, for the cha
/archives//html/Topband/2004-05/msg00067.html (6,742 bytes)

22. Topband: ESP QSO's--new way of working? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 22 Jun 2004 22:52:03 -0000
I've seen this happen numerous times, over the years. Someone stateside sees the callsign of a dx station, and calls, even though they can barely hear him....or has heard part of a call....and he has
/archives//html/Topband/2004-06/msg00069.html (7,460 bytes)

23. Topband: Two band antenna (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 22 Jul 2004 17:07:56 -0000
I had good success with a 160/80 elevated GP in Vermont. The lower 63' of the antenna was made from 450 ohm transmitting open wire line. The top was #12 insulated superflex. I started with 68' of OWL
/archives//html/Topband/2004-07/msg00042.html (7,313 bytes)

24. Topband: sloper interaction (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 4 Dec 2004 10:08:59 -0500
Dave, You can't have both slopers up at the same time, that close together, without interaction. Pull the 9INN back alongside the tower, and coil it up at the bottom, and try the experiment again. Se
/archives//html/Topband/2004-12/msg00055.html (7,818 bytes)

25. Topband: sloper antennas (score: 1)
Author: jimjarvis@comcast.net
Date: Sun, 05 Dec 2004 19:58:00 +0000
If a quarter wave sloper is merely a method for feeding a tower..... what happens if you have multiple 'slopers', like radials around the tower? K3ANS has an "inverted sloper system"....where the tow
/archives//html/Topband/2004-12/msg00080.html (7,808 bytes)

26. Topband: How'd you measure that? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Mon, 3 Jan 2005 11:19:21 -0500
snip Bill Tippett, W4ZV, of New London, NC correctly copied code word OMAHA from the N2XE beacon transmitting with a peak carrier power of .0000406 watts. snip Let's see, here.... that would be 40.6
/archives//html/Topband/2005-01/msg00029.html (7,058 bytes)

27. Topband: S meter reality check (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 8 Jan 2005 13:36:07 -0500
Until we insist on meters being calibrated in dBm, rather than S units, this discussion is meaningless. dBm can be calibrated in a receiver. If in doubt...what's an S unit? In whose receiver? Under w
/archives//html/Topband/2005-01/msg00139.html (6,868 bytes)

28. Topband: JA sp/lp from east coast (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Tue, 8 Mar 2005 12:31:21 -0500
N1BUG's post concerning a JA sked raises a question. My first JA qso's on 40 and 80, from a modest station, were long path. This occurs in December/January, when east coast US sunset and JA dawn coin
/archives//html/Topband/2005-03/msg00094.html (7,198 bytes)

29. Topband: LP/Skew/ Geoclock? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 13 Mar 2005 13:20:23 -0500
Folks, Interesting discussion about LP vs. Skew. Truly critical to know where to point our topband yagis, to make sure we aren't working SP by mistake. Seriously, though... does anyone NOT run geoclo
/archives//html/Topband/2005-03/msg00150.html (7,191 bytes)

30. Topband: (no subject) (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 7 Apr 2005 09:19:46 -0400
Hello gents Just checked the tower. 140Ft shunt fed tower free standing. Shunt fitted at 30ft. tapping point suggested by Earl. single wire shunt. 1800 = 1- 1.2 1825 = 1 -1.2 1850 = 1 - 1.1 1875 = 1
/archives//html/Topband/2005-04/msg00065.html (7,031 bytes)

31. Topband: broadband vertical cages (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 7 Apr 2005 13:55:24 -0400
There is considerable literature on the topic of cage style vertical radiators. The navy has done extensive work with them, in pursuit of submarine communications. As Tom and Herb observed...the prin
/archives//html/Topband/2005-04/msg00082.html (7,312 bytes)

32. Topband: battle creek special? (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 7 Apr 2005 14:03:20 -0400
In response to the inquiry about a portable lowband antenna... I've seen mention of the battle creek special, without having seen a source for details. My assumption is that it's a segmented tubular
/archives//html/Topband/2005-04/msg00083.html (6,707 bytes)

33. Topband: LDE's & temporal dispersion (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Thu, 7 Apr 2005 16:31:37 -0400
With due respect to all comments, and the work of Dicke, Penzias, et.al. ... (not to mention W8JI)... I have heard LDE's and multipathing at various times on 40m, in the now 47 years that I've been h
/archives//html/Topband/2005-04/msg00085.html (7,905 bytes)

34. Topband: 80/160 inv. L (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sun, 10 Apr 2005 13:11:10 -0400
This may or may not prove more sanitary than adding a trap to a 160M L, to provide 80m coverage: In VT, I had a dual band, elevated ground plane...the top 10' of which had to fold over, so it was sor
/archives//html/Topband/2005-04/msg00104.html (7,310 bytes)

35. Topband: short vertical (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Fri, 19 Aug 2005 13:15:16 -0400
Chip, Herb's comment regarding cancellation is real. You could raise the base impedance, and wind up with a nicely matched ineffective antenna. I would shorten the wires up to maybe 15', and run the
/archives//html/Topband/2005-08/msg00026.html (7,459 bytes)

36. Topband: May 2005 EET article about the DLM (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Sat, 20 Aug 2005 21:24:42 -0400
I thought we'd skewered this nonsense back in May, but perhaps it was on the towertalk reflector. Critical comments about URI are in order. The notion that this shortened vertical contains any new te
/archives//html/Topband/2005-08/msg00049.html (8,550 bytes)

37. Topband: tuning elevated radials (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Fri, 16 Sep 2005 12:55:38 -0400
Ford, Questions and comments. Q: I like the rf probe idea...and I think I can draw the circuit you created...but rather than speculate, can you either send me something directly...or post here if eas
/archives//html/Topband/2005-09/msg00039.html (8,256 bytes)

38. Topband: switching coax shields (score: 1)
Author: "Jim Jarvis" <jimjarvis@comcast.net>
Date: Wed, 5 Oct 2005 12:27:28 -0400
"As a general rule that is a problem. I would never switch the shields in my station. It is begging for problems! The shields should be solidly grounded to a common groundplane. Only the centers swit
/archives//html/Topband/2005-10/msg00019.html (7,010 bytes)


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