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Marantz 2235B popping

Thank you for the feedback

- For the differential pair I used KSA992FBU, Hfe matched
- For H706 I found there a defective 2N1711 from Texas, I replaced by a 2N1711 the pin out is ebc; the recommended 2SC875 is surprisingly ebc as well,
I gave up with BC140,
- the H717 andH730 diodes have been changed as you mentioned by two 1N4148 in series,
- the zener diode H715 was tested ok as well as the H005,
- the output transistors have been replaced: H714 and H712 have been replaced by by MJ21193 and MJ21194

I have no explanation why I found - 0,32V on base of H708 and H710 where it should be 0V.
Any idea?
 
Hello,

Here we are, as everything looked OK, I decided to re solder most of the P 700 right channel solder.

Minimum one solder was not good I cannot tell which one (s), but what I can tell is the following the offset is nicely adjustable down to zero, the bias is 8 mV and the 2235B is singing nicely.

Thank you for your support

Alain
 
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