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281. Re: Topband: Noise cancellers performance (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 12 Sep 2008 15:19:41 -0700
I have an ANC-4. It is a MASSIVE key click generator if you put it inline with your transmitter. Other than that it works. :) This is caused by the circuit that detects when you're transmitting and d
/archives//html/Topband/2008-09/msg00033.html (7,538 bytes)

282. Re: Topband: K9AY loop, pennants on the beach (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sat, 20 Sep 2008 13:44:07 -0700
They've also got my Hercules II, which runs on 13.8VDC, and will get them up to about 500W output. 73, Jim K9YC _______________________________________________ Topband mailing list Topband@contesting
/archives//html/Topband/2008-09/msg00052.html (6,912 bytes)

283. Re: Topband: (more related question) How electrically tall is this tower please? (will it work on 160?) (long read) (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sun, 28 Sep 2008 23:23:00 -0700
MANY variables, including the vertical and horizontal directivity of the antennas AND the propagation of horizontally and vertically polarized waves. Example: I have a 160M dipole at 100 ft that is b
/archives//html/Topband/2008-09/msg00073.html (9,419 bytes)

284. Re: Topband: [Topband] Inverted "L" vs." T" (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 08 Oct 2008 23:00:41 -0700
Yes. 73, Jim K9YC _______________________________________________ Topband mailing list Topband@contesting.com http://lists.contesting.com/mailman/listinfo/topband
/archives//html/Topband/2008-10/msg00059.html (8,487 bytes)

285. Re: Topband: Shunt Fed Tower (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sat, 11 Oct 2008 08:00:49 -0700
Use one of my coaxial chokes (use the instructions for 80M-160M) on the feedline of the 40M antenna, placing it roughly halfway between the top of the antenna and the earth. This will take the feedli
/archives//html/Topband/2008-10/msg00090.html (8,453 bytes)

286. Re: Topband: EWE 160m (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 14 Oct 2008 08:42:43 -0700
Why not go to the source -- K9AY has plenty of stuff on the internet. Google to find it. 73, Jim K9YC _______________________________________________ Topband mailing list Topband@contesting.com http:
/archives//html/Topband/2008-10/msg00102.html (7,064 bytes)

287. Re: [RFI] Computer RFI on 160 (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 29 Oct 2008 13:14:35 -0700
I wouldn't expect it to. You need at least 14 turns on a single # 31, and more turns or more toroids in the stack is better. Use my measured data for RG8X on these cores as a starting point. In essen
/archives//html/Topband/2008-10/msg00158.html (8,521 bytes)

288. Re: Topband: Beverage antenna ground (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 31 Oct 2008 08:37:30 -0700
On both of my two reversible Beverages built with DXE hardware, I bond the DXE boxes to the 8 ft ground rods, and I use a serious coaxial choke tuned to cover 160M and 80M to isolate the coax from th
/archives//html/Topband/2008-10/msg00179.html (7,870 bytes)

289. Re: Topband: 1:4 Guanella (current) balun experiences ? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Mon, 03 Nov 2008 08:53:30 -0800
The higher power rated DX Engineering 1:4 baluns are two ferrite core (Fair-Rite #31) wired in series on the 4 side and parallel on the 1 side. This sort of design is superior to air core, because it
/archives//html/Topband/2008-11/msg00020.html (8,981 bytes)

290. Re: Topband: small diaameter radials - issues? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sat, 15 Nov 2008 10:06:15 -0800
It will depend on soil chemistry (PH) and physical abuse. The literature pretty much agrees no difference at all. Another point -- the only reason to bury radials is a mechanical one. They work fine
/archives//html/Topband/2008-11/msg00095.html (7,551 bytes)

291. Re: Topband: Feedpoint voltage (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Mon, 17 Nov 2008 22:44:16 -0800
Don't assume that you MUST use a specialty capacitor. I'm tuning my top-loaded vertical with a parallel combo of some fixed caps that I bought at a surplus house in Silicon Valley for under a buck ea
/archives//html/Topband/2008-11/msg00109.html (8,498 bytes)

292. Re: Topband: Not so Boring QSO (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 19 Nov 2008 07:18:37 -0800
I'm just south of San Francisco, and often active on topband in the hours before sunrise. It is VERY common to hear both JA and UA0 during those hours (and also after midnight, around their sunset).
/archives//html/Topband/2008-11/msg00118.html (8,118 bytes)

293. Re: Topband: HV disc capacitors (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 19 Nov 2008 10:35:13 -0800
That's entirely possible. It's a HUGE surplus warehouse (like there used to be on S. Michigan Ave in Chicago 40+ years ago) with probably a million or more different items. They're about an hour fro
/archives//html/Topband/2008-11/msg00127.html (7,225 bytes)

294. Re: Topband: Multiple Beverage Grounding (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 20 Nov 2008 11:41:37 -0800
I don't consider myself an expert on the common grounding aspect of it, but I would be inclined NOT to bus them together. One thing I strongly recommend is a SERIOUS coax choke on each coax that come
/archives//html/Topband/2008-11/msg00133.html (7,220 bytes)

295. Re: Topband: Choke baluns (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 20 Nov 2008 14:51:14 -0800
These are vastly inferior to the chokes I've recommended. That is, my coaxial choke designs will provide MUCH greater isolation between the Beverage and the coax. 73, Jim Brown K9YC _________________
/archives//html/Topband/2008-11/msg00137.html (7,355 bytes)

296. Re: Topband: SERIOUS coax choke (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 20 Nov 2008 16:35:33 -0800
Yes, it should go at the feedpoint. If the feedline is long, you might want another one further along the line so that it doesn't interact with other antennas. Yes, the intent is to isolate the feedl
/archives//html/Topband/2008-11/msg00138.html (7,707 bytes)

297. Re: Topband: SERIOUS coax choke (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 21 Nov 2008 09:30:43 -0800
Because the wire in question is long enough to behave as an antenna at some frequencies of interest. The portion of the coax betwen the choke and the intentional RX antenna will act as a separate ant
/archives//html/Topband/2008-11/msg00148.html (9,546 bytes)

298. Re: Topband: Choke baluns (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 21 Nov 2008 12:25:10 -0800
No, only that few transformers are ideal, that the capacitance may not be symmetrical from one winding to the other, that more decoupling is better, and that practical results confirm that a choke he
/archives//html/Topband/2008-11/msg00150.html (7,893 bytes)

299. Re: Topband: 160m dipole help wanted (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Mon, 24 Nov 2008 10:08:12 -0800
The loading coils made by Hypower Antenna Company work very well for me at 100 ft. The overall antenna length is about 170 ft. The antenna is designed to work on 80 and 160. I also have a 40M fan ele
/archives//html/Topband/2008-11/msg00196.html (7,534 bytes)

300. Re: Topband: New CQ160 contest Rules (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 28 Nov 2008 11:25:02 -0800
The skewing of many contest rules in ways that benefit the east coast tends to depress activity on the west coast. The Stew is a great example of working to find a better way. No surprise -- the cont
/archives//html/Topband/2008-11/msg00269.html (8,025 bytes)


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