Sherwood S-8300Cp receiver help

[Wayne Tiffany]

I have posted a copy of the schematic at
http://www.kcswug.com/images/\Sherwood S-8300Cp receiver schematic.pdf for
anyone that is interesting in offering an opinion.

I agreed to look at this receiver for friends of ours. Short version - she
said it didn't work. I said to check fuses, she did and found the external
speaker fuses blown. Replacing them didn't fix the problem.

Ok, I opened it and found that Q710R, one of the main outputs is shorted.
And Q706R & Q704R are both missing part of their housing, as in probably
exploded out due to overcurrent.

My question is this. Based on your experience, what else should I be
checking? I ask because I hate to miss changing something due to lack of
experience, but I also hate to just shotgun everything in that output area.
I figured that I should probably replace all 4 of the outputs even though
they are not shorted. I will check ESR on the electrolytics. What about
the transistors 708 & 709 feeding the outputs? Thoughts?

Thanks.

Oh, for those interested, on that web site I also have pictures of an old
stand-up radio that I acquired. At this point it's in my garage, but
hopefully some day I will have the time to restore it.

WT

 

[Wayne Tiffany]

"Wayne Tiffany" <wayneRMVJNKtiffany@MOREJNKasi.com> wrote in message
news:496b8771$1@news.x-privat.org...

I have posted a copy of the schematic at
http://www.kcswug.com/images/\Sherwood S-8300Cp receiver schematic.pdf for
anyone that is interesting in offering an opinion.

I agreed to look at this receiver for friends of ours. Short version -
she said it didn't work. I said to check fuses, she did and found the
external speaker fuses blown. Replacing them didn't fix the problem.

Ok, I opened it and found that Q710R, one of the main outputs is shorted.
And Q706R & Q704R are both missing part of their housing, as in probably
exploded out due to overcurrent.

My question is this. Based on your experience, what else should I be
checking? I ask because I hate to miss changing something due to lack of
experience, but I also hate to just shotgun everything in that output
area. I figured that I should probably replace all 4 of the outputs even
though they are not shorted. I will check ESR on the electrolytics. What
about the transistors 708 & 709 feeding the outputs? Thoughts?

Thanks.

Oh, for those interested, on that web site I also have pictures of an old
stand-up radio that I acquired. At this point it's in my garage, but
hopefully some day I will have the time to restore it.

WT
I finally have time to try to work on this again over the weekend - anyone

have suggestions for me? Thanks for your time.

WT