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Total 541 documents matching your query.

221. Re: [Amps] ARRL Amplifier book (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Sun, 05 Sep 2004 17:14:58 -0400
At 04:02 PM 9/5/2004, Phil Clements wrote: The new "toys" of the 21st century are the big amps from Collins that are coming out of the old Nike missile silos, Big Henry amps that came out of U.S. emb
/archives//html/Amps/2004-09/msg00082.html (8,482 bytes)

222. Re: [Amps] SB-220 (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Wed, 03 Nov 2004 12:52:23 -0500
Just a couple of thoughts: Not all SB-220s are prone to parasitics. I suspect that a lot depends on how well they were built in the first place. I have one with Eimac tubes in it that has been uncond
/archives//html/Amps/2004-11/msg00037.html (10,573 bytes)

223. Re: [Amps] SB-220 (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Wed, 03 Nov 2004 13:50:53 -0500
Will, that was absolutely NOT what I was saying. Of course, parasitics do happen, and amplifier designers do install parasitic suppression if their design proves to be prone to them, The stock SB-220
/archives//html/Amps/2004-11/msg00040.html (14,291 bytes)

224. [Amps] vacuum relay failure (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Mon, 22 Nov 2004 10:02:46 -0500
I modified my SB-220 about 5 years ago with vacuum relays on the input and output. It has had a lot of hard contest use since then without incident, but this weekend, after about a half hour, I notic
/archives//html/Amps/2004-11/msg00367.html (8,006 bytes)

225. Re: [Amps] vacuum relay failure (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Mon, 22 Nov 2004 11:17:29 -0500
I do not use this amplifier QSK, and have it set up with a speed-up circuit in any case. Normally, I run 20-30 Ms of PTT delay to protect the relays, but that's not really practical with hand keying.
/archives//html/Amps/2004-11/msg00370.html (9,906 bytes)

226. Re: [Amps] vacuum relay failure (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Mon, 22 Nov 2004 12:26:07 -0500
Interesting. Thanks, Vic. I know it was the output relay because the grid and plate meters on the amp were still swinging -- in fact, probably over-swinging because of the unloaded state. I had an ar
/archives//html/Amps/2004-11/msg00374.html (9,313 bytes)

227. [Amps] Advice on instruments for ham use (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Tue, 23 Nov 2004 13:33:36 -0500
I'm interested in acquiring a used solid-state oscilloscope for ham use. I know this isn't the place to ask, but hope that people who hang out here can point me to a ham radio homebrew or similar mai
/archives//html/Amps/2004-11/msg00390.html (7,440 bytes)

228. RE: [BULK] - [Amps] Advice on instruments for ham use (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Tue, 23 Nov 2004 13:44:19 -0500
Well, it's more a question of wanting to have one so that I can learn how to use it, but not one that is so limited that it doesn't have much real-world application. I have a rough idea of what that
/archives//html/Amps/2004-11/msg00392.html (9,536 bytes)

229. [Amps] SB-220 relays fixed; questions (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Mon, 29 Nov 2004 15:55:57 -0500
Thanks for comments on my previous post. I replaced both vacuum relays in my modified SB-220 this weekend, and have just been testing. As a result I have a few questions. I'm really just curious, rat
/archives//html/Amps/2004-11/msg00456.html (9,598 bytes)

230. [Amps] negative grid current (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Wed, 01 Dec 2004 17:29:00 -0500
I'm still puzzling over why my SB-220 would suddenly be showing *negative* grid current when in transmit but with no drive applied. Resting plate current is nominal, but grid meter deflects below zer
/archives//html/Amps/2004-12/msg00010.html (6,750 bytes)

231. Re: [Amps] Dx pedition amp ??? (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Thu, 02 Dec 2004 14:28:08 -0500
I don't think anyone has mentioned the FinnFET amps. 9 kg for a 1KW amp plus power supply isn't too shabby. See <http://www.kunnallislehti.fi/finnfet/ff-1001>. A mere $4K, including travel case. 73,
/archives//html/Amps/2004-12/msg00034.html (10,928 bytes)

232. Re: [Amps] Unknown tube amp (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Sun, 12 Dec 2004 11:41:01 -0500
304TLs? 73, Pete N4ZR At 10:52 AM 12/12/2004, Vic Rosenthal wrote: Chris Howard wrote: The PA has two tube sockets. They are a two-pin push-in-and-twist mount. Each also has two plate-cap type connec
/archives//html/Amps/2004-12/msg00182.html (7,675 bytes)

233. Re: [Amps] sb220 question after mods (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Sun, 16 Jan 2005 11:57:52 -0500
A propos of this -- what does it signify if the grid meter reads well below zero when an SB-220 is idling at no drive? 73, Pete N4ZR At 11:31 AM 1/16/2005, Vic Rosenthal wrote: N7uvh@aol.com wrote: H
/archives//html/Amps/2005-01/msg00304.html (8,790 bytes)

234. Re: [Amps] ? 3-500Z Repair (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Thu, 10 Feb 2005 07:08:01 -0500
Works great -- both tubes currently in my amp have resoldered pins. 73, Pete N4ZR At 10:51 PM 2/9/2005, Ron wrote: Ron wrote: Hello to the Group, Does anyone have a fix for a melted solder joint on t
/archives//html/Amps/2005-02/msg00393.html (8,128 bytes)

235. Re: [Amps] New FET's (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Thu, 10 Feb 2005 07:29:36 -0500
A dozen or more years ago, I was involved in a project to fly a space science instrument on a Soviet spacecraft (my part in the project was diplomatic, not technical). It used a solid-state memory un
/archives//html/Amps/2005-02/msg00394.html (10,219 bytes)

236. Re: [Amps] AL-1200 VS AL-1500 (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Fri, 25 Feb 2005 14:36:41 -0500
Actually, it is probably neither. Here's why. I am the guy who programmed the database and its searches, using FrontPage. I am NOT a skilled programmer. The data are free-form, in each field, so, for
/archives//html/Amps/2005-02/msg00828.html (9,059 bytes)

237. Re: [Amps] Liquid Cooling Systems (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Fri, 11 Mar 2005 07:31:30 -0500
Boy, that's a great site -- lots of info on issues like the relationship between % of glycol and cylinder head temperature, which strikes me as very analogous to anode temperature in an amp. 73, Pete
/archives//html/Amps/2005-03/msg00282.html (8,949 bytes)

238. Re: [Amps] RJ1H (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Wed, 16 Mar 2005 07:07:35 -0500
Having just killed a Kilovac HC-1 (equivalent to the RJ-1A) in my modified SB-220 due to hot switching, I am interested in whether the RJ-1H might prove more resistant to operator errors. 73, Pete N4
/archives//html/Amps/2005-03/msg00370.html (10,442 bytes)

239. [Amps] Running 3-500s upside down (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Wed, 16 Mar 2005 08:14:12 -0500
I understand that running 3-500s on their side risks internal shorts. I need to do some trouble-shooting on my modified SB-220's relay/bias switching circuit, however, which would be much facilitated
/archives//html/Amps/2005-03/msg00372.html (7,133 bytes)

240. [Amps] Mine is bigger than yours (was: Re: Standby tubes (was: Evenmore power solid-state amp's)) (score: 1)
Author: Pete Smith <n4zr@contesting.com>
Date: Sat, 02 Apr 2005 15:43:50 -0500
All this WLW stuff is fun, but I believe that VOA still has a few of their 1 megawatt medium-wave transmitters left, and there was a reference in www.worldofradio.com to a 2-megawatt medium-wave stat
/archives//html/Amps/2005-04/msg00047.html (8,604 bytes)


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