First time posting...need help
I recently acquired the preamp. Very sweet sound, paired with the Adcom GFA535.
All inputs work fine, but turntables only play the left channel.
What I have done so far: with an oscilloscope, I checked the signal path all the way to the COM outputs of the IC531 (it should give me an amplified signal on 13th contact of the IC, but it doesn't. The opamp IC502 is fine, it spits the amplified signal of the phono on the 6th contact and I can still see the signal in the 18th contact of the IC531. The CD and Tapes/Video work fine. Only the output of the right channel of the IC531, when playing the phono, is dead.
My question is: is it possible that the IC531 (TC9152P) is faulty only in that input (18th contact)?
There is also another issue but I think they are totally unrelated: the tuner signal indicator bars shows good signal on local radio stations, but the sound is horrible. All radio stations sound pretty crappy. I have a 300ohm T antenna connected to it and all my other receivers work fine with it.
Anyone?
Thanks in advance
I recently acquired the preamp. Very sweet sound, paired with the Adcom GFA535.
All inputs work fine, but turntables only play the left channel.
What I have done so far: with an oscilloscope, I checked the signal path all the way to the COM outputs of the IC531 (it should give me an amplified signal on 13th contact of the IC, but it doesn't. The opamp IC502 is fine, it spits the amplified signal of the phono on the 6th contact and I can still see the signal in the 18th contact of the IC531. The CD and Tapes/Video work fine. Only the output of the right channel of the IC531, when playing the phono, is dead.
My question is: is it possible that the IC531 (TC9152P) is faulty only in that input (18th contact)?
There is also another issue but I think they are totally unrelated: the tuner signal indicator bars shows good signal on local radio stations, but the sound is horrible. All radio stations sound pretty crappy. I have a 300ohm T antenna connected to it and all my other receivers work fine with it.
Anyone?
Thanks in advance
Your logic appears correct. Suggest check solder connections on IC531, yeah a long shot.
IC532 appears to be for tape monitoring, ie, mostly unused, maybe consider a swap, but
then you might have 2 damaged parts. Our good friends in china will sell you fake IC's
via that auction site...
IC532 appears to be for tape monitoring, ie, mostly unused, maybe consider a swap, but
then you might have 2 damaged parts. Our good friends in china will sell you fake IC's
via that auction site...
Thank you very much! The tip of swapping the IC is excellent and I didn't think about it!
Now, in case, for some reason I end up with both bad ICs, do you have a go-to supplier for old parts. I have heard horror stories about fake Chinese chips, are other suppliers anymore reliable?
Now, in case, for some reason I end up with both bad ICs, do you have a go-to supplier for old parts. I have heard horror stories about fake Chinese chips, are other suppliers anymore reliable?