output ports, C-72

[nh36000]

All;

I have a pre here that doesn't output signal at all, now. I get a power hum from it when it's powered up. There are two ports in back and I've plugged in to the variable port, the other is a fixed volume output.

I get one half an ohm reading between each channels grounds, vari and fixed, everything else is open but, the circuit between right channel hot and left channel ground, of the fixed port. Instead of open, I get a reading of, say, 26.5 Meg.

This could be the cause of the buzz I hear when it's powered up and the fact that the volume pot has no affect on listening volume. Last week I could source a tape deck and I would have to turn the decks output all the way down and then turn the left channel up to maybe, one half of one. Normal listening volume then but I know that it's not right. I would turn the right channel up about half way to full volume to get the two outputs to match volumes.

There is a short in there somewhere in the RCAs.

Has anyone worked on one of these to help me remedy this?

Lu.

 

[nh36000]

A thousand pardons, please!

I just had a look at the plug ins on the back of the amp. I had the deck ins plugged into the 'play' pair and the decks outs going to the 'audio in' LD ports. Just one set to the left, each.

No wonder it was buzzing.

I saw 12 views so far, I'll delete these two in a week.

Sorry for the post but I've been trying to figure this out since Tuesday night.

Lu.