Sir ericzhao . . . . .
What it seems like you have found yourself there, is being a ceramic bisque encased 0.1 motherfarad . . .0.1 ufd . .paper bypass capacitor, being at a 400VDC voltage rating .
OBSERVATIONS AND ANALYSIS . . . .
One of the photos of what seems to be the most visible of 2 other like units, shows its left lead wire going to the bare tinned ground buss wire and its other left lead going towards the BLACK encased power strip resistor that is heat sink strapped to the metal chassis for enhanced power handling capacity.
The large black power transformer . . .RCA identifier 274 . . .also tells of a factory dating of the 36th week of 1949 and I see what looks like to be (2) 6V6GT audio output tubes and a tubes and and a far end, possible, 5Y3 rectifier tube, being barely visible.
Had the other option of this transformers 936 code date possibility have been for 1959, I would have expected those 6V6 tube pairs to have been all glass subminiature 7 pin 6AQ5's .
Need to know the RCA model of the 16MM ? projector unit, for further info on that audio amplifier, the capacitor in query, should properly test as open circuit . . . .so just grasping for straws in suspecting that unit as being the root cause of the audio problem.
One other thing noticed is that there is either being a lights reflection on the side of the top of the black power resistor, about 1/5 the way down OR possible a bulge outward in the plastic case from internal overheating.
If one section of that two section resistor is open, it will kill the amp.
Also give the units other tubes . . . . . like possibly 6SL7 or 6SK7 or 6SJ7's, etc.
73's de Edd
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