Philips GA 212 Power Supply Problems -- voltage too high

[ignis-fatuus]

So I've been working on this Philips 212 recently. I picked it up and it seemed to work OK as is powered up and I could select between 33 and 45, etc. I didn't think much of it. There were two axial electrolytic caps that I decided to replace. Upon removing the PCB one of the trim pots simply fell apart (R467, 4.7k trim pot) which I will be replacing shortly. I noticed, however, that the controls seemed kinda finicky and figured I should check my voltages.

The manual notes that the power supply, metered between the chassis and the supply, should be tuned to -9v via the trim pot R472. To my surprise, the voltage I am currently seeing is closer to -15v. From what I can tell, the voltage regulation is accomplished two transistors--(TS405) AD162 and (TS441) AC127-- and a couple of diodes. I suspect that one or both transistors have failed but I'm unsure as to how to test them. If anyone has any advice, it would be much appreciated. Furthermore, if anyone knows of some good replacements for the AC127/AD162, that would also be of a lot of help.

Dunno if this helps but here's some more voltage readings:

TS441
Expected | My Readings
e -0.78v | -0.88v
b -0.71v | -1.-17v
c +7.4v | -0.21v

 

[ignis-fatuus]

OK, so I've been mucking about a bit and I am beginning to think the trim pot R472 is the issue. All of the trim pots seem to be in pretty bad shape and I suspect they all should be replaced with modern equivalents. I suppose it makes sense as I had a different trim pot (R467) disintegrate and fall apart while lifting the PCB. After a bit of fiddly tweaking of R472 I was able to get the supply voltage to where it should be. I certainly hope it's not the transistors as the two germanium packages do not look like they're easy to come buy these days.