sansui r 70 problem

shageedawg

New Member
well i have an old sansui r 70 integrated reciever/amp and i get no volume from it.the dial face lights up but i don't get any volume when i hook up speakers.the only fuse i have found is a 5 amp fuse and the filament is intact.all the caps look fine and haven't popped.so what do you guys think?is there another fuse i am missing?i just did a little job on my sears audio amp and i know there were three fuses inside that one,so i thought maybe i had missed a fuse in the sansui.any thoughts?thanks in advance
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thanks for the response,but i am a bit of a layman and no tech ,so i just do whatever simple repairs i can.explain please?
 
Sansui R-70

Pardon my ignorance but your model is newer than I thought and will probably have a switch to connect the pre and main amps. It could be on the side. Move it back and forth a few times and see if you get power. If you do, spray it with the Deoxit and push the switch back and forth about 20 times to loosen the corrosion. If it still acts up periodically, you have to open the case and spray the Deoxit on the inside of the switch. Hope this helps.
 
does it need jumpers from pre main ?

Since your model is newer, it probably has a switch, possibly on the side, that connects and disconnects the pre and main amps. Make sure the switch is in the connected position. If it is, try my advice on loosening any corrosion in the switch.
 
so theres no switch,but here's a few nudies of the transformer and a teeny bit of corrosion perhaps on the underside of the main circuit board.plus a look at the caps
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well wouldn't ya know it?seems it works after all!but i only get the right channel,and not the left.i managed to pick up a radio signal,so i will try something else in the morning.
let me make a correction.it barely works.i originally thought it was the test speaker,an old hitachi i didnt care about,but i tested it with a good speaker and its not the cheap speaker or lack of an antenna.i have one blown channel and then a really staticky channel with hardly any power
 
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do you have a test meter ? .. can you get hold of deoxit or the equivalent ? first start with cleaning controls if no test meter ..if you have test meter check the dc voltage at the speaker out terminals ..it should be in mv
 
Yeah, count me in on the controls cleaning theory. You have to have a square one to start with, and that would be all the switches and controls passing a signal through as they should. Until you are sure, its all just conjecture. If you havent already done this, then theres a sticky at the top of General Audio forum that maps things out very well.
Now..Im going to tread on some shaky ground here.IMHO, if a cleaning didnt bring this back from the grave, and its nothing like the tape monitor switch is in gear, then maybe thats where that project should stop. Its a piece from far after Sansuis golden years and can be replaced with something of equal or greater sonic value and quality for very close to no money.Like hit the thrift on the right day and for 10 or 15 bucks voila.
Just my opinion (and Kenny Rogers, "You gotta know when to hold em, know when to fold em") mind you, but maybe something to think about.
 
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