View attachment 73623
A friend is somewhat attached to this old stereo.
He bought it while serving special forces in Vietnam.
The finals (lower) were replaced 20 years ago. Possibly by me. Seems familiar! They were generic.
I found an original set of 4 on Ebay and replace the same two again. Also replaced one driver. (circled) with something similar from junk box.
Each side (dc supply) is fed with an external 5A fb fuse.
That seemed to fix the amp which is his main concern.During one "power up" while working on the AM/FM, both are very low sensitivity and output, speaker made a loud thump and blew one final again.
It seems there are issues in the final amp circuit, and I only have one spare transistor.
Will my mismatched driver be suspect?
Output caps?
If I don't get any good ideas here, I'll order a good set of 2sc756, and hope for the best.
Originally I told him it was not worth repair, and he was OK with that. He has since given me something in trade, so I want to give it my best shot.
A friend is somewhat attached to this old stereo.
He bought it while serving special forces in Vietnam.
The finals (lower) were replaced 20 years ago. Possibly by me. Seems familiar! They were generic.
I found an original set of 4 on Ebay and replace the same two again. Also replaced one driver. (circled) with something similar from junk box.
Each side (dc supply) is fed with an external 5A fb fuse.
That seemed to fix the amp which is his main concern.During one "power up" while working on the AM/FM, both are very low sensitivity and output, speaker made a loud thump and blew one final again.
It seems there are issues in the final amp circuit, and I only have one spare transistor.
Will my mismatched driver be suspect?
Output caps?
If I don't get any good ideas here, I'll order a good set of 2sc756, and hope for the best.
Originally I told him it was not worth repair, and he was OK with that. He has since given me something in trade, so I want to give it my best shot.
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