On the top of an R-20 amp there's a tall power resistor, R59, right next to the rectifier tube, but electrically separated by a 50 ohm R66. R59 is effectively two power resistors, a 5500 ohm and a 100 ohm. Mine is cracked.
Symptom is that all tubes glow ( 6v rail working fine ), but zero sound comes out(no crackle, no hiss). I suspect this cracked resistor is the culprit, as its a series part of the DC regulation stage. Effectively, the tubes have no DC to work with(untested assumption)
Is there a source for these? Anyone have one they'd let go of? Would love to keep it looking original.
Alternatively, would it be a big problem to replace it with a 5600 ohm and a 100 ohm? What power ratings would these need to be? Which side is the 5600 ohm(I assume this heads toward the FM receiver), which side is the 100 ohm(Assume this heads towards the PA / output transformer)?
Symptom is that all tubes glow ( 6v rail working fine ), but zero sound comes out(no crackle, no hiss). I suspect this cracked resistor is the culprit, as its a series part of the DC regulation stage. Effectively, the tubes have no DC to work with(untested assumption)
Is there a source for these? Anyone have one they'd let go of? Would love to keep it looking original.
Alternatively, would it be a big problem to replace it with a 5600 ohm and a 100 ohm? What power ratings would these need to be? Which side is the 5600 ohm(I assume this heads toward the FM receiver), which side is the 100 ohm(Assume this heads towards the PA / output transformer)?