Troubleshooting Magnavox 9304-10

[csparks75]

I did manage to hear a tiny bit of static this morning. I'm excited to plug directly into it this afternoon to see what happens.

 

[century tek]

Must have been shadow play on that one pic. Looks fine now. Yeah, let's hope the amp is pretty much ok for now and dead silent, but try it with a phone or CD player just to see if you get any sound.

If so then your tuner-preamp would need some attention.

 

[csparks75]

Ok! I have audio. It's not great. Starts fairly strong then degrades over the course of 30 seconds. Ohm Readings on the OTs are in spec (140ohm blue, 160ohm Brown) for both. Attached is picture of the backside. Black to common on speakers in cabinet, green to Orange in the cabinet and yellow to Brown in the cabinet. V5 still red plating, sprayed some deoxit to clean them up. Deoxit didn't help, so I guess now I need to just go through everything and make sure they match the schematic. Can I remove the red plating tube while I test everything else?

 

[csparks75]

After looking at the schematic and more pictures, I think I found why V5 was red plating. I attached R21 to pin 6 of V4 instead of pin5. Oops. There's my stupid error. Circled in the picture.

 

[csparks75]

After fixing that blunder, the amp now lives and plays pretty strong. Thanks for all the help! Next step, get the receiver up and running! It's still not working.