Motor repair for Goldmund Studio TT /w Pabst motor


Well, either I am seriously forum challenged (a possibility) or for the second time my thread on this subject has been removed and is not in the archives. I thought they archived everything, but I guess not. Moderator, could you please stop deleting this. Every time you do I lose all the posts from forum members.

I sent my motor to an electronics firm in California recommended by a friend in the industry. They took one look at it and wouldn't touch it because it had electronics in it and, I guess, they don't do that stuff.

The good news seems to be that the motor windings are very likely ok and the problem actually seems to be related to the internal electronics parts.

Since I saw smoke come out of the motor during my initial investigation of the problem, I had thought the windings were compromised. Removing the bottom cover of the motor reveals a circular circuit board but also visible through a gap where the wires enter the motor are some additional electronics parts. So, when the motor was returned to me I set about disassembling the damn thing myself. In addition to removing the bottom cover, this required removing a couple of C clips and other various bits.

I was expecting to see some heat damage but everything looks fine. There are a lot of Caps, Resistors, Transistors and other three terminal devices in this thing. I am leaning toward the theory that one or more of these transistors have failed and I will be testing them to see if I can locate the problem.

Word on the street has been that Pabst of Germany went out of business in the early '80s. However, in the latest issue of TAS I noted that the review of the Raven AC 3 TT mentioned that it uses a Pabst motor.
willster
"Both turntables suffer (identically) from thin bass response, and resonance issues."

Wow, not my experience at all. My Studio has amazing bass, solid foundation. Never thin. And zero resonance issues. Tried Sorbothane once and it killed dynamics and energy. Became clinical. Also the T3, once it is set up and tightened down can't really change so again, I'm not having the same experience you are.
My friend had à goldmund reference and problems with the Electronic. Waiting for repair he adapted the teres rim drive and the sound Was far better. I don t know if it is possible to adapt it on the studio.
Anyone; my Goldmund ST4 arm goes up upon actuation but doesn't stay up and goes down again. I know/think it has to do with the microswitch in the back but how do you fix it? while we're at it, do you know anyone who repairs them ?
If you think you might want to ship, you could try ringing audiocraftsman. Mike is a really good no nonsense tech and unafraid of a challenge. 

http://audiocraftsman.com