[Boatanchors] HRO-50 Audio Issue

[Joe Connor]

I'm making progress on this set, but I've encountered a puzzling audio problem. The symptom is low audio output. 

When I remove one of the 6V6s, the audio drops greatly. When I remove the other, it has no effect on the audio output. Ordinarily, I would suspect a bad audio output xformer, but I have the proper plate and screen voltages on both 6V6s. Both 6V6s test good and I've substituted known good 6V6s with no change. I've replaced all the caps and out-of-spec resistors in the 2nd AF stage. It appears the audio output xformer is a replacement. 

Any ideas? A link to the Rider's schematic is attached below.

As always, thank you for your help and guidance. 

Joe Connor


http://www.nostalgiaair.org/PagesByModel/395/M0012395.pdf