Old receiver - high DC offset - no manual/schematic - bias test point & voltage?

I believe so. There is just one large filter cap, and there are 47 volts across it's terminals.
 
I can see only one wire going directly from the rectifier to that cap which is to it's pos. terminal.

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The 20-ish gauge red one that the wood skewer is "pointing" to. There are only two diodes. Is this still referred to as bridge rectifier?
 
It lives

I got it working on AUX and TUNER but discovered it had a dead channel on PHONO. There were five electrolytic capacitors and two pairs of 2SC644's that I replaced and it seems one of capacitor's legs formed a bridge to another pad on the PC board. Solder maintained the bridge on one side but not the other. Easy fix once I knew what the problem was.

The receiver sounded OK on AUX and TUNER but PHONO sounded like crap so that's why I did wholesale replacement of the pre-amp - there was not really a lot on there. I am actually surprised that it sounds as good as it does. Am listening to it now through the $2 Boston Acoustics A70's I just re-foamed.

Supposedly made by what would later become Rotel but I think it's got an old Sansui or HK vibe to it. It's not as pretty as a Sony STR6045 I have but sounds like it has about the same amount of power - 18WPC.

If it is of 1968 vintage, it's the oldest SS piece I have.

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Good work there, Gary. Some of the looks of your receiver reminds me of my Kenwood KA-2000 from circa 1973.



Nando.
 
Cool looking receiver!

I have an old ass one I would like to see work again, how many of you have seen this Sansui TR-707A before? It's their first solid state receiver. Just makes weird noise in one channel and the other is silent

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Northwinds said:
Cool looking receiver!

I have an old ass one I would like to see work again, how many of you have seen this Sansui TR-707A before? It's their first solid state receiver. Just makes weird noise in one channel and the other is silent

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ogS6RRe.jpg
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Capacitor coupled output to the loudspeakers...
 
Is that good or bad Joe? I had a Pioneer SX-626 that was cap coupled though I have no clue what that means

Also, what are the 3 little transformers for?
 
IIRC THUMP CONTROL

Keeps the nasty pops from yer speaks.
 
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