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1. Topband: Rx antennas (score: 1)
Author: (K9AY)
Date: Mon, 6 Jan 2003 19:23:46 -0600
HOw important is FRONT END protection of transceiver receiver I am using KW + on Top Band and about to install some pennants about 120 ft from transmit antenna Josh n7xm high desert of Nevada -- Josh
/archives//html/Topband/2003-01/msg00035.html (7,407 bytes)

2. Topband: K9AY Loop Revisited (score: 1)
Author: (K9AY)
Date: Fri, 13 Dec 2002 13:16:31 -0600
de W8JI... Feedline isolation will rarely be needed with the K9AY loop. In the several installations of my personal versions, the feedline and antenna have both been connected to ground, with no ill
/archives//html/Topband/2002-12/msg00199.html (8,859 bytes)

3. Topband: K9AY Loop Revisited (score: 1)
Author: (K9AY)
Date: Fri, 13 Dec 2002 16:37:15 -0600
Hi Tom, Comments below... I do not normally share the model I use for the K9AY loop, since it knowingly violates some NEC-2 modeling rules in order to obtain a reasonable correlation to observed beh
/archives//html/Topband/2002-12/msg00201.html (8,442 bytes)

4. Topband: More K9AY Loop Modeling (score: 1)
Author: (K9AY)
Date: Mon, 16 Dec 2002 20:54:40 -0600
After recent discussions on the Topband and Antennaware lists, I took = some time to review modeling of the K9AY Loop. At the suggestion of = WX0B, I took another look at an accepted ground model for
/archives//html/Topband/2002-12/msg00217.html (8,104 bytes)

5. Topband: K9AY Center support (score: 1)
Author: (K9AY)
Date: Thu, 21 Nov 2002 20:54:27 -0600
-- Tom and fellow Topbanders, My modeling exercises suggest that a grounded metal mast will degrade the pattern significantly. It will still have some F/B, but the peak F/B in the null will be reduc
/archives//html/Topband/2002-11/msg00130.html (8,680 bytes)

6. Topband: K9AY Center support (score: 1)
Author: (K9AY)
Date: Fri, 22 Nov 2002 12:43:11 -0600
-- Tom I first modeled the K9AY loop on 160M with the published dimensions (25 ft overall height), with the terminating resistor adjusted for the deepest null. I use the "real ground" option because
/archives//html/Topband/2002-11/msg00140.html (8,697 bytes)

7. Topband: 160 Vertical (score: 1)
Author: K9AY" < (K9AY)
Date: Thu, 17 Oct 2002 21:54:34 -0500
etc... -- -- My estimate is similar to Earl's...I hope resonance is even lower, because: If your tower is close to 1/2-wave, you may have trouble obtaining a shunt-feed match without extremely high
/archives//html/Topband/2002-10/msg00063.html (8,683 bytes)

8. Topband: chicken wire ground screen (score: 1)
Author: K9AY" < (K9AY)
Date: Sun, 1 Sep 2002 12:54:39 -0400
-- Dave and all, Mesh conductors are not a significant problem. Radar and satellite antennas often use perforated reflectors to save weight. At the lower 'microwave' frequencies, grid reflectors are
/archives//html/Topband/2002-09/msg00010.html (8,745 bytes)

9. Topband: Flag Xfmr Measurements End Game (score: 1)
Author: K9AY" < (K9AY)
Date: Mon, 23 Sep 2002 14:38:22 -0400
-- I can verify Tom's above assertion. When designing my TRX-16 16:1 transformer, I tried making a two-stage design -- a low-loss (tightly coupled) 16:1 XFMR plus a choke 'balun.' It did not work we
/archives//html/Topband/2002-09/msg00168.html (7,665 bytes)

10. Topband: Silent Feedline for RX antennas (score: 1)
Author: K9AY" < (K9AY)
Date: Mon, 26 Aug 2002 11:15:24 -0400
-- Tom is right. Balanced line is not a "silver bullet" fix for feedline pickup. And he is right that it can make matters worse -- any added complexity introduces new opportunities for problems. To
/archives//html/Topband/2002-08/msg00094.html (8,766 bytes)

11. Topband: K9AY loop (score: 1)
Author: K9AY" < (K9AY)
Date: Thu, 13 Jun 2002 09:58:31 -0400
-- And, of course, my own web site: 73, Gary K9AY
/archives//html/Topband/2002-06/msg00021.html (7,771 bytes)

12. Topband: QRP DX (score: 1)
Author: K9AY" < (K9AY)
Date: Sat, 29 Jun 2002 11:58:30 -0400
-- I have operated 7 or 8 160M contests at 5 watts, as well as DX contests with QSOs on 160. All but one was done with either a shunt-fed 75 ft. tower on a city lot, or an inverted-L of the same hei
/archives//html/Topband/2002-06/msg00064.html (8,377 bytes)

13. Topband: Feeding rotating towers (score: 1)
Author: K9AY" < (K9AY)
Date: Fri, 24 May 2002 17:53:25 -0400
-- I've heard of a couple installations with wire antennas hung from the stationary ring of the bearing, so they don't move with the tower. This would work for a shunt feed or skirt wire, with a loo
/archives//html/Topband/2002-05/msg00166.html (7,379 bytes)

14. Topband: Antenna interaction (score: 1)
Author: K9AY" < (K9AY)
Date: Tue, 30 Apr 2002 10:20:37 -0400
W8JI noted: For those of you who wonder how much separation is enough to avoid interaction and distortion of the radiation pattern, I offer this story from my earlier career in broadcast consulting:
/archives//html/Topband/2002-04/msg00076.html (8,984 bytes)

15. Topband: Power Coupling on 160 meters (score: 1)
Author: K9AY" < (K9AY)
Date: Tue, 30 Apr 2002 23:10:12 -0400
You might be right, Bud, but it's more likely that those Texans were listening in another direction using Beverages or other directional RX antennas and did not hear you calling. I have rarely had t
/archives//html/Topband/2002-04/msg00088.html (7,537 bytes)

16. Topband: Source of Vactrol device for K9AY loop (score: 1)
Author: K9AY" < (K9AY)
Date: Mon, 11 Mar 2002 20:10:03 -0500
-- Lionel and all, The K9AY Loop systems I am making have three selectable resistances: 560, 464 and 408 ohms -- the 1500 and 2700 ohm resistors are switched in parallel with the 560 ohm resistor. T
/archives//html/Topband/2002-03/msg00109.html (7,936 bytes)

17. Topband: Ewe, Flag, and Pennant questions for the experts (score: 1)
Author: K9AY" < (K9AY)
Date: Fri, 22 Mar 2002 14:41:23 -0500
A few additional comments in the discussion of RX antennas: The broadband feedpoint Z, termination and pattern of K6SE's optimized pennant and flag designs is quite elegant. I'll repeat the usual cau
/archives//html/Topband/2002-03/msg00215.html (9,185 bytes)

18. Topband: VP6DI on 160 (score: 1)
Author: K9AY" < (K9AY)
Date: Sun, 24 Mar 2002 20:40:28 -0500
I just got through to VP6DI on 15M (0130Z) -- they said they had an inverted-L up and ready to go. I gather that it's not the antenna that was used (and damaged) at VP8GEO, but that's FB with me as l
/archives//html/Topband/2002-03/msg00235.html (6,300 bytes)

19. Topband: Shortend Vertical model questions (score: 1)
Author: (K9AY)
Date: Mon, 11 Feb 2002 16:42:53 +0000
Tony Tom W8JI's comments are good, and my 2 cents is that your modeling is "in the ballpark" concerning bandwidth, feedpoint Z and increased loading inductance as it is placed higher on the structure
/archives//html/Topband/2002-02/msg00041.html (8,993 bytes)

20. Topband: Shortend Vertical model questions (score: 1)
Author: K9AY" < (K9AY)
Date: Tue, 12 Feb 2002 17:15:37 -0500
Yes, this is a situation to avoid. For a short vertical like the one under discussion, the easiest way to avoid the problem is to model the larger vertical section using 3 or 4 wires the same size a
/archives//html/Topband/2002-02/msg00054.html (9,042 bytes)

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