Recent content by Sfpeter69

What I was hoping is to find someone familiar with these as the service manual is more of a cheat sheet and doesn't say much about the preamp regardless. And as I mentioned already, I swapped the tubes that drove each channel and the transistors between each channel board--still the right...

I cleaned the pots, switches, and sockets, and adjusted the bias on the tubes. It's just the preamp right channel isn't amplifying the signal.

I have Mac 1500 that in general is running well, except for the phono preamp. I had assumed the right channel was simply out, but when I played a line level input through it with the balance all on the right side I am getting a signal, it just doesn't appear to be amplifying it. The left...

I have a MAC 1500 I was given (as in free) a year or so ago. It had been in an attic and I assumed it as bad/dead. This week I decided to work on it, after adjusting the amp tubes (the voltages were all over) and cleaning it I found the only real problem when using it on everything but FM is...