[sdiy] EMS VCS3 II negative power supply problems

[Mattias Rickardsson]

Hey,

I'm trying to revive a VCS3 II where the power supply has issues on the
negative regulation. With an incoming -25 V it puts out roughly -24 V
instead of the supposed -9 V. Does anyone have experience with similar
problems?

(The transformer was fried on the negative half, so I'm running it from a
bench supply. I have also replaced the regulating 741 and TIP3055 power
transistor)

((The phutney.com site and its very readable schematics also magically
disappeared, which didn't help)) :-)

Best,

/mr
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