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Help With Pioneer Sa-9800 Please

It is working!!!

I changed the 47uf 63v caps on the PSU board and the power amp boards for 47uf 100v. Transistors are:

Q1&Q2= MJE340
Q3 = BC640
Q5&6 =2N4338
Q4&Q8 = 2N5401
Q7 = 2N5551
I checked the current going to the Power Amp on the -52v lines and they were both 11.4ma.

Hope that is that!!!

Many thanks for your help-much appreciated.
 
That is EXCELLENT news!!

Plus the 11.4 mA current drain to the amplifiers is also very good news.

Those 63 volt capacitors are probably the weakest link on the board, considering what voltages the raw DC can rise to. I have seen several now that leaked just enough current (not goo) to overheat the power supply, destroying the regulators.

Those 100v caps should be hard to hurt.

I am keeping a record of your replacement transistors that worked, to help any others in the UK who have a need for similar parts.
 
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