08-08-2019, 02:14 AM
as i search for a "d" cell for the simpson i read all the 77 tube voltages.with 118 vac at the the plug p-k (2-5) on the osc.was 245 vdc and 100vdc on sg-k (3-5) while the 2nd 77 p-k had 50 vdc 20 volts low.and sg-k (3-5) was 29 vdc. as far as correcting the 20v low after checking the resistors i cant find any fault and none run real hot.i can only assume that the tube is dragging it low. so few parts and so hard to find. i dont suppose that ancient .0014 mica cap is suspect even tho i know mica caps last forever.
