[Heathkit] Apache TX-1 Audio Mods

[Robert & Linda McGraw K4TAX]

I've noticed in several articles indicating that the audio coupling capacitors C64, C61 and C60 were changed to 0.01mfd paper caps.  Originals were disk ceramic and typically 510 pf.  In looking further at these changes, I see that the input cap C66 is original at 0.005 mfd.  Would there be any reason or benefit to changing this cap to a 0.01 as well?  Also, adding self bias {cathode R and bypass} to the input stages at V7 and increasing the value of R48 to 4.7 meg should help to clean up the front end.

Comments and thoughts appreciated.

73
Bob, K4TAX