- 1. Re: [Amps] Value, part 3 (final) (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sat, 16 Jul 2011 08:28:53 -0700
- Hi Allen, This isn't so outrageous. I just sold a bunch of used 4-1000A's for an estate. All I could test were the filaments, and I had a buyer who was willing to pick them up. I sold them for $25 ea
- /archives//html/Amps/2011-07/msg00189.html (8,055 bytes)
- 2. [Amps] Need -- 300 ohm 50w noninductive resistor (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Tue, 19 Jul 2011 19:57:47 -0700
- I'm looking for a 300-ohm 50w non-inductive resistor. I'm going to try the G2DAF circuit with a pair of 4-400As and this is for the grid resistor. -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ __
- /archives//html/Amps/2011-07/msg00226.html (6,514 bytes)
- 3. Re: [Amps] Need -- 300 ohm 50w noninductive resistor (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Wed, 20 Jul 2011 13:17:48 -0700
- Thanks, they don't stock 300/50w but I could get five 1500/10w, which would work. -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ _______________________________________________ Amps mailing list A
- /archives//html/Amps/2011-07/msg00241.html (8,162 bytes)
- 4. [Amps] Some PS questions (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Fri, 22 Jul 2011 11:32:25 -0700
- 1) I'm building an amplifier with a separate power supply with the negative output isolated from ground to allow for plate current metering. The meter will be located in the RF unit. Where should the
- /archives//html/Amps/2011-07/msg00264.html (6,831 bytes)
- 5. [Amps] TL-922 --> 21st century (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sat, 13 Aug 2011 14:22:06 -0700
- I have a stock TL-922 that I want to update. I'm going to do the following: -- step start -- vacuum relay QSK -- automatic bias switching to cut off tubes when not keyed -- check / adjust filament vo
- /archives//html/Amps/2011-08/msg00053.html (7,012 bytes)
- 6. Re: [Amps] TL-922 --> 21st century (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sun, 14 Aug 2011 07:56:38 -0700
- I would worry about a fuse in series with the plate supply. If it blows and if you continue to apply drive, wouldn't there be a possibility of toasting the grids? -- Vic, K2VCO Fresno CA http://www.q
- /archives//html/Amps/2011-08/msg00057.html (9,039 bytes)
- 7. Re: [Amps] TL-922 --> 21st century (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sun, 14 Aug 2011 08:53:11 -0700
- The W8JI article quoted by G8TIC explains what they thought they were doing and why Tom thinks it's a bad idea: <http://www.w8ji.com/vhf_stability.htm> I'm going to make the non-controversial mods I
- /archives//html/Amps/2011-08/msg00061.html (9,650 bytes)
- 8. [Amps] TL922 mods (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Fri, 26 Aug 2011 13:16:02 -0700
- I have my TL-922 on the air. I added a soft-start relay, vacuum relay QSK, and a bias switching circuit to cut the tubes off in between keyed elements. I also strapped the grids directly to ground (W
- /archives//html/Amps/2011-08/msg00196.html (8,773 bytes)
- 9. Re: [Amps] TL922 mods (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Fri, 26 Aug 2011 13:52:03 -0700
- I meant to say "a 5 ohm resistor between the input circuit and the capacitor feeding RF to the filaments", not the grid. -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ ____________________________
- /archives//html/Amps/2011-08/msg00198.html (6,856 bytes)
- 10. Re: [Amps] 756P3 + TL 922A (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Mon, 19 Sep 2011 20:06:14 -0700
- 1) Vacuum relay (or similar) QSK is a necessity, even if you are an SSB operator who uses VOX or a CW operator who never uses full QSK. The 922 is /designed/ to hot-switch the t/r relay in those situ
- /archives//html/Amps/2011-09/msg00134.html (8,555 bytes)
- 11. [Amps] TL-922 loading capacitor (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sat, 08 Oct 2011 07:56:45 -0700
- The TL-922 loading capacitor 'wants' to be at more than maximum capacity at the low end of 160 and 80m. Has anyone added additional capacity, and if so, how much? I'm thinking of adding a 500 pf "fly
- /archives//html/Amps/2011-10/msg00015.html (7,049 bytes)
- 12. Re: [Amps] TL-922 loading capacitor (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sun, 09 Oct 2011 15:20:52 -0700
- With a dummy load, the capacitor is at maximum capacity on 1815 kHz when tuned for maximum output. Actually it is a hair above maximum on 3515. -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ _____
- /archives//html/Amps/2011-10/msg00022.html (8,922 bytes)
- 13. Re: [Amps] TL922A Choke Alternative (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Wed, 09 Nov 2011 14:39:12 -0800
- This is the easiest part to obtain that there is: nothing. I connected all of the grid pins in my TL922 directly to ground with the shortest possible straps. See W8JI's discussion here <http://w8ji.c
- /archives//html/Amps/2011-11/msg00044.html (9,594 bytes)
- 14. Re: [Amps] HIGHWAY LOUIE (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Mon, 21 Nov 2011 14:11:31 -0800
- Don't forget W6AM. He had, I think, a pair of 813's in his trunk. I worked him when I was a kid in the late 1950's from NY, on 20m CW when he was mobile. -- Vic, K2VCO Fresno CA http://www.qsl.net/k2
- /archives//html/Amps/2011-11/msg00100.html (9,426 bytes)
- 15. Re: [Amps] On Behalf of K4BOF (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Fri, 25 Nov 2011 08:45:36 -0800
- Yes, that is exactly the way to do it! :-) I also highly recommend grounding all of the grids directly, as W8JI suggests. I've been using a modified 922 for a few months now and am very happy with th
- /archives//html/Amps/2011-11/msg00133.html (8,910 bytes)
- 16. Re: [Amps] On Behalf of K4BOF (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sat, 26 Nov 2011 22:12:12 -0800
- I grounded my grids separately to the existing ground posts that were around the tube. I did not use the socket hardware. The straps could have been slightly shorter if I'd drilled holes right near t
- /archives//html/Amps/2011-11/msg00150.html (15,413 bytes)
- 17. Re: [Amps] home brew 811a amp - need some advice (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Sun, 18 Dec 2011 08:18:23 -0800
- My guess is that moisture in the transformer caused an insulation breakdown. I've seen recommendations here in the past for how to dry out a transformer before use. If it was stored in a damp locatio
- /archives//html/Amps/2011-12/msg00138.html (10,771 bytes)
- 18. Re: [Amps] [rfamplifiers] Re: Xmas special offer upadate( warranty and pictures) (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Wed, 21 Dec 2011 08:00:45 -0800
- If what we are talking about is the transformers, a transformer rated for 50 Hz will work fine at 60 Hz -- in fact, it will run cooler. The opposite is not necessarily the case, especially with large
- /archives//html/Amps/2011-12/msg00175.html (9,921 bytes)
- 19. Re: [Amps] SB-1000 160 m power down (score: 1)
- Author: Vic Rosenthal <k2vco.vic@gmail.com>
- Date: Thu, 22 Dec 2011 09:56:55 -0800
- Very interesting. Evidence that you always need to measure inductance of toroids at the operating frequency. Vic _______________________________________________ Amps mailing list Amps@contesting.com
- /archives//html/Amps/2011-12/msg00192.html (9,126 bytes)
- 20. Re: [Amps] 3cx800a7 Grid Current Problem (score: 1)
- Author: Vic K2VCO <k2vco.vic@gmail.com>
- Date: Thu, 26 Jan 2012 08:37:06 -0800
- The stock 922 apparently isn't optimal at the low end of 160 (or 80). I had to add some capacity across the loading capacitor to get a reasonable match on mine, but output is still low compared to ot
- /archives//html/Amps/2012-01/msg00202.html (10,962 bytes)
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