Phono Stage OPAMP

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I have a phono stage with a rather mysterious opamp, it´s labeled SSMf69PH. belongs to a Musical Fidelity X-LPS v3. Of course it has two of them, one for each channel. I have been having problems with my right channel and after contacting MF for support, which was not good, I decided to open it up and go at it with a multimeter. Result of this was that even though I passed a small signal (TT like) through the Phono Stage the opamp behaved erratically, it would not give me a fixed voltage output on a fixed 1kHz input. I would have thought it should produce a higher voltage 1 KHz output and that was it, the other side was doing just that btw. I do not know whether this is because some other component surrounding it is faulty, but I could not identify it, or because the opamp had failed. I have tried finding the data sheet for this part, but it is nowhere to be found. I emailed and called MF but they would not or could not tell me who made them.

So I have hit a brick wall. I am wanting to replace the opamp, but don´t know with what to replace it.

I would like to know if there is any way by which to identify what type of opamp it is, what gain it should have, and any other key characteristics in order to find a suitable replacement ???

I am not technically experienced in electronics but have enough common sense to figure things out as I go. I can solder and desolder, and have built a couple of hobby kits and other things, made circuits with eagle and now I´m playing around with Arduino ATM to automate my fish tank. So if correctly guided I can fix this, I am certain.

As I said I have no data sheet, don´t know for sure what pin is for what, although I have "identified the schematic" and am trying to work it out.

I thank you for any advice.

Manolo
 
I guess that you are going to have to reverse engineer the OPAMP circuit to determine the pin-out. Most OPAMPS have common pins, but some are different as well.
"SSMf69PH"? SSM was used by Precision Monolythics, now ADI, so that my be a clue.
I do not identify the part based on the part # sorry!!

Rick
 
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