PL400 Series one (Misbehaving channel)

[lazio2000]

Hello members,

I have been working on this unit for a while. One channel is showing high DC voltage on the terminals. The other channel is working fine.
The differential pair transistors have been swapped with NTE199, the output transistors are MJ series. The BIAS on the bad channel is stuck at 350 mv and not adjustable.
I took some voltages at the pins of the differential pair transistors and they are very different one channel to another. Unit has been fully recapped, the emitter resistors are good.

 

[mlucitt]

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