Wanted to get some opinions on the next step for restoring a Fisher 460T/A and MPX-70 console pull. brought it up slowly on a variac, added power tubes at 90 VAC, best I got out of it was some static/noise while adjusting the volume, along with a very faint hum/signal, but not the signal that I was inputting. I'm slightly behind the 8-all in that the knobs and faceplate are missing, so I don't have a good feel for the control operation. I did just buy a 440T with knobs and faceplate, and am hoping that the controls are identical, since the placement and number of knobs is identical. However, I'm a bit stumped at the next step. One of the paper caps on top of the amp did get warm, so i will be buying at least one 100uFD/250V cap, along with whatever caps might need replacing in the underside. Once I have finished this step, where do I go then??? I was thinking of removing the MPX unit from the circuit, and trying to find an appropriate input for a digital signal...
Thanks,

Analog Addict

100 uFD/350 volt cap coming. Once replaced, I'll fire it up again and see what happens. I may have to try the phone input without the MPX unit onboard...

Hope you get it up and runnning. I have nothing to offer as my tube knowledge is very very limited.

Partial success. I got the big cap on the amp replaced, and tried using a Walkman as an input source. Beautiful music ensued...
However, the preamp is only putting out one channel and that is slightly distorted. I need to go through the preamp and prolly recap it....

sweet. hope the work on the pre goes as well.

Well, apparently it's not completely healthy...There is a bit of crackling going on in the background, seemingly intermittantly. I'm led to believe it's possibly a plate load resistor or a cathode resistor, or perhaps a tube socket or even a tube issue. I have tried a second set of EL84's in it with no change. Next is to pull the two 7247 driver tubes and see if it still crackles...Any other suggestions/advice?

Thanks....

Pre-amp is next on the list...