I managed to harvest a few pics of 1960 (?) Pioneer SM-Q140 Tube Receiver off the net ... includes the original box, schematic and owner's manual ... thought they might be useful for future reference.
Pioneer SM-Q140 Tube Receiver
- Thread starter Chip - HP
- Start date
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Interesting. I noticed from the pictures of an SM-Q140 on ebay, that this unit has one larger output transformer and another somewhat smaller one - both driven from one pair of output tubes via a selector switch. From looking at the schematic posted in this thread, it appears that the amplifier operates in class AB in mono mode and class A in stereo. I had an SM-B200 (asian not USA export) when I was a kid. I wish I could find one now.
Phasephreak
New Member
Hi Paul! Did you ever find one?
Phasephreak
New Member
there are 2 output transformers in the SM-B200 and the SM-Q140. I have the set (1 power and 2 output transformers ) from a scrapped B200 in a bin on my parts rack.
Phasephreak
New Member
Hi Paul. I have several B-200 available. One is fresh back from my tech - a true plug n play. The other has been a shelf queen for over 30 years. They are both reasonably priced. I too share a fondness for the B200 - it was my first true stereo "hi-fi" amp. Hence my repurchase of a number of them and it's cousin, the B-201A.
