"Derwin" wrote in message
news:6mzYh.5305$Dq6.3498@edtnps82...
I tried to re-cap a tube receiver (amplifier + tuner), and now when I turn
it
on it starts playing music for a few seconds after it warms up, then the
music
fades out and and hum takes over. I don't really know what I'm doing, and
the
wiring inside looks like a mess of spaghetti. I'm pretty sure I replaced
the
caps properly, but I used .068uf WIMA caps to replace .050uf wax/paper
caps,
and I'm wondering if the value difference, added up over 8 caps would make
a
difference? Other than that, does anyone have any advice based on my
description of the unit's behavior? Any comments whatsoever might be
helpful..

Maybe a tube has gone west ... internal leakage caused by mechanical
disturbance when working on it? Tubes get hot and sometimes cathode leakage
follows a brief warm-up period.

Also, you did not mention the voltage ratings of the capacitors.

Often, hum is caused by the power supply filter caps but your symptoms don't
quite fit that.