Just use what you see in other circuit diagrams - frequently 220uF. Do you
understand their purpose? They are there to give what is essentially a rock
solid above-ground DC reference. The only time the voltage across it should
change is while the capacitor is first charging. It charges until it is
sufficiently high above the grid voltage that the tube stops conduction,
thus biasing the tube.
Ken
>
>Does anyone have any formulae or have any guidelines in determining
>the size of a cathode bypass cap?? I am interested in both directly
>and indirectly heated cathodes.
>
>Thanks :)
>
>
>
>
>Yahoo! Groups Links
>
>
>
>
_______________________________________________________________________
Ken Stone
sasami@...Modular Synth PCBs for sale <
http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <
http://www.blaze.net.au/~sasami/>