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References: [ +from:vic@rakefet.com: 418 ]

Total 418 documents matching your query.

261. Re: [Amps] Ameritron al80a (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Sun, 16 Mar 2008 22:30:39 -0700
The AL80B choke is designed to move the series resonance away from 17m. It should work and avoid this problem. It wouldn't hurt to check it in place with a grid dip meter, if you have one available.
/archives//html/Amps/2008-03/msg00146.html (7,228 bytes)

262. Re: [Amps] Henry 2K-3 PS Mod (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Fri, 21 Mar 2008 13:15:23 -0700
According to the 3-500z data sheet <http://home.c2i.net/clank/ham/pa/3-500z.html>, class AB2 operation at 3000v requires a cathode voltage of +10v, with 3500v requiring +15v. The 2K3 schematic shows
/archives//html/Amps/2008-03/msg00195.html (8,024 bytes)

263. Re: [Amps] Retraction with regard to the SB220 (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Fri, 28 Mar 2008 10:26:03 -0700
Speaking of the parasitic suppressors, Heath used carbon composition resistors which often increase in value over time -- especially if they have overheated, which can happen if the amp is used heavi
/archives//html/Amps/2008-03/msg00320.html (8,184 bytes)

264. Re: [Amps] SB220 "A" mods (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Sat, 29 Mar 2008 08:04:25 -0700
Not the speakers...the transistors in the audio amplifier driving them! The RF is picked up on the speaker wires. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ________________________________
/archives//html/Amps/2008-03/msg00334.html (9,086 bytes)

265. Re: [Amps] Relays (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Mon, 31 Mar 2008 08:04:56 -0700
Deterioration of the receive contact is the way they have failed for me. I had one last about 2 years and another that is still going after possibly 7 years (the amp is in the hands of another operat
/archives//html/Amps/2008-03/msg00386.html (9,656 bytes)

266. Re: [Amps] Relays (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Tue, 01 Apr 2008 16:28:09 -0700
The cost of the diodes and associated circuitry is more than a cheap relay. And they are susceptible to damage from lightning-created transients. I had an Alpha 86 with pin-diode switching that worke
/archives//html/Amps/2008-04/msg00024.html (7,180 bytes)

267. Re: [Amps] Relays (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Wed, 02 Apr 2008 09:05:28 -0700
The RJ-1 type of relay can also be completely silent if you mount it with a few drops of silicone seal or on a piece of soft rubber. Mount it directly to metal if you like to hear it click! -- 73, Vi
/archives//html/Amps/2008-04/msg00038.html (8,086 bytes)

268. Re: [Amps] Relays (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Wed, 02 Apr 2008 11:42:01 -0700
Yes, absolutely. I forgot to mention that I make connections to the relays with thin strips of copper foil (0.002" thick, cut to about 1/8" width). I bought a big roll of this at a hobby shop. The co
/archives//html/Amps/2008-04/msg00042.html (8,661 bytes)

269. Re: [Amps] Planning to resurrect Ameritron AL-80 (no A/B) (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Tue, 06 May 2008 21:10:31 -0700
You will need to replace the plate RF choke with the AL-80B version or remove some turns to move a resonance away from 17 meters. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ________________
/archives//html/Amps/2008-05/msg00071.html (6,909 bytes)

270. Re: [Amps] Need help understanding an old Transformer (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Mon, 26 May 2008 09:55:43 -0700
It is what you would get from a choke-input filter and a full-wave rectifier with the ct grounded. No! The spec is saying that you could draw 500 mA from the abovementioned full-wave center-tap circu
/archives//html/Amps/2008-05/msg00195.html (8,693 bytes)

271. Re: [Amps] little OT, but here goes . . . (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Sun, 22 Jun 2008 08:06:06 -0700
If God had meant for me to use SSB, he would have given me one nostril. -- Steve Fried, K2PTS (SK) -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco _______________________________________________
/archives//html/Amps/2008-06/msg00178.html (7,148 bytes)

272. Re: [Amps] Air variable pitting - repairable? (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Sat, 19 Jul 2008 14:09:27 -0700
If the capacitor is the type that you can take apart the individual plates, you can file it smooth, and then polish it on a buffing wheel. I've done that successfully with SB-220-type tuning caps. --
/archives//html/Amps/2008-07/msg00155.html (8,345 bytes)

273. Re: [Amps] Air variable pitting - repairable? (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Sat, 19 Jul 2008 15:06:57 -0700
That's why I said polish it on a buffing wheel. How did they get the mirror finish in the first place? -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ___________________________________________
/archives//html/Amps/2008-07/msg00158.html (8,098 bytes)

274. Re: [Amps] Wire (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Mon, 28 Jul 2008 10:19:11 -0700
My experience when feeding a balanced antenna with a common mode choke at the transmitter end is the following: reducing the reactive component at the balun terminals reduced heating. I am not sure w
/archives//html/Amps/2008-07/msg00337.html (8,469 bytes)

275. Re: [Amps] Solid State Relays in Plate Supply Primary (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Mon, 04 Aug 2008 07:58:48 -0700
You need to keep RF out of them! I had one controlling a pair of Astron 70 amp 12v supplies for an 800 watt solid state amplifier, and the supplies mysteriously blew fuses when transmitting. The reas
/archives//html/Amps/2008-08/msg00017.html (7,872 bytes)

276. [Amps] 3-500Z glitch resistor (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Sun, 07 Sep 2008 07:21:27 -0700
Everyone seems to agree that a glitch resistor between the plate choke and the HV supply is a good idea, to limit huge current surges due to arcs caused by gas, etc. But recommendations for the value
/archives//html/Amps/2008-09/msg00033.html (6,962 bytes)

277. [Amps] Quieting SB-1000 fan (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Wed, 17 Sep 2008 08:06:17 -0700
I was lucky enough to pick up a very nice SB-1000 recently -- actually it was purchased by a friend at an estate sale in unfinished condition, so it was unused! It also had the corona washer and a ne
/archives//html/Amps/2008-09/msg00174.html (6,618 bytes)

278. Re: [Amps] Transformer reliability? 34yr old Collins... (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Thu, 02 Oct 2008 12:56:02 -0700
If it is not potted and has been sitting in a damp place it may have absorbed moisture, which could cause insulation breakdown later. I am not sure what the best way is to dry it out, but someone wil
/archives//html/Amps/2008-10/msg00010.html (7,385 bytes)

279. Re: [Amps] What is wrong with my Alpha? (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Mon, 10 Nov 2008 14:48:51 -0800
I would look at the output of all three of your transceivers on a scope to verify that there isn't a power spike when keyed. Some transceivers put out 150 watts or more for a few ms when keyed, even
/archives//html/Amps/2008-11/msg00106.html (7,915 bytes)

280. Re: [Amps] SB-221 parasitic supression upgrade kit (score: 1)
Author: Vic K2VCO <vic@rakefet.com>
Date: Thu, 20 Nov 2008 13:50:58 -0800
I would agree with all of the above and add that the arc could be occurring in the tube, if it is gassy. Parasitic oscillations rarely (if ever?) cause arcs anyway, so this is probably the least like
/archives//html/Amps/2008-11/msg00201.html (8,703 bytes)

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