[Amps] 6m amp based on W1QWJ

[Paul Decker]

Thanks everyone, great information, 



The sure did look like DC blocking, so I guess they would be effective at blocking RF as well.   The symbol threw me into a tail spin though, try to find that in a schematic symbol list! 



I would have thought that 50 or 75v even would be just fine, but maybe they are trying to build in a safety factor, or as you say, they don't come in smaller values. 



I think changing to DC would mean that the feed through caps couldn't be used as wouldn't they block DC?   I would have to change them to be more like a bypass cap to shunt RF to ground rather than block DC.   One of the things I was thinking with DC is that it is very easy to wire up a simple voltage regulator to dial in the filament voltage exactly.  That is a bit harder with AC.   Once I have a nice DC voltage regulator for the filaments, I could then easily power other circuits since (ideally) I will have stable voltage at the tube.   -- anyway, that is where I was going with that, if it makes sense. 



I am adapting this project somewhat.  One of my goals is to build it with the one tube as it is specified, but I also want the capability to add another 3cx800 if/when I get one.   To that end, should I run 4 feedthrough caps, or can I just use the two and put the second tube in parallel with the first through the same feed through caps? 



Thanks, 


Paul (KG7HF)