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previous: Roger That 22K might take care of the pre... -- 11/16/1997 6:02 AM

Re: Silverface champ

11/16/1997 12:18 PM
Tony Taliaferro	Re: Silverface champ Your right, the change is for the preamp voltage. I haven't tried the output tube mod yet, but it sounds interesting. The Q & A thang you referred to is in the older book (first book) on page 221 & 222. Cool idea! What he's doing is dropping 56V off the B+ by grounding it through the zener diode. Remember it'll have to be reverse-biased with the cathode connected to ground (the place where you'll remove the center tap). It won't have to be the $10 zener (50 watts) though since a champ is only 5 watts or so. If you want to go from 420V to 350V you'll have to drop about 70V. Try a 1N5373 5 watt zener diode and see what happens. Matter of fact I think I'll try it too! See Ya!

11/16/1997 12:18 PM

Tony Taliaferro

Re: Silverface champ

Your right, the change is for the preamp voltage. I haven't tried the output tube mod yet, but it sounds interesting. The Q & A thang you referred to is in the older book (first book) on page 221 & 222. Cool idea! What he's doing is dropping 56V off the B+ by grounding it through the zener diode. Remember it'll have to be reverse-biased with the cathode connected to ground (the place where you'll remove the center tap). It won't have to be the $10 zener (50 watts) though since a champ is only 5 watts or so. If you want to go from 420V to 350V you'll have to drop about 70V. Try a 1N5373 5 watt zener diode and see what happens. Matter of fact I think I'll try it too!
See Ya!

Replies:

Bruce This is just a clarification commen... -- 11/17/1997 8:37 AM