Vestax PMC 25 schem?

[guitardad]

LOL, I'm getting the good stuff in lately. No prints, parts NLA... urggggggghh

Thought I'd check here and ask anyway! Luck has to change sometimes.

[Enzo]

Vestax appears to be still in business, have you contacted them?

[guitardad]

Vestax appears to be still in business, have you contacted them?

Yes. Both UK svc and JP service. I'll give them a couple days before I panic.

This think was badly burned up on a generator according to the customer. He borrowed it from another guy.

It's got opamps popped (physicaly split) on every board and both 9V reg's are split open, 3 traces open. Gonna be fun!

Might be best to shotgun the IC's cheap enough anyway. 20- 4558's, 6- 4580's, 4- 082d's.

[g1]

This is one of those rare cases where to not shotgun everything running on that supply would compromise reliability and be a disservice to the customer.
Been there, got beat .

[guitardad]

Vestax replied "sorry we are not in the business of handing out schematics. that is old unit customer should buy a new one"

LOL

Yeah I shotgunned all the IC's and regulators, and a couple ps caps. Took about 1.5 hr. It works to an extent. That being a real oddity. For CH 1 side for Lines 1 and 2 and phono, I get a nice R ch Main Out, but a somewhat distorted L ch Main Out with very little low end. On CH2 side, it's the exact opposite.

Been one of those weeks!

[J M Fahey]

Vestax replied "sorry we are not in the business of handing out schematics. that is old unit customer should buy a new one"

I remember when Japanese used to be polite.

You should cut and paste their answer and post it on every DJ Forum in the planet.
No kidding.

[Leo_Gnardo]

Vestax replied "sorry we are not in the business of handing out schematics. that is old unit customer should buy a new one"

LOL

From the Vestax products I've seen they're in the business of copycatting other manufacturers equipment. I have a Vestax dual gate that's a dead nuts copy of a Drawmer. So when it breaks, I guess I'll just consult the Drawmer schematics that are readily available. If you can figure out whose gear they copied, might try the same.

And if you email them back, let 'em know the customer will be buying a new unit that's NOT A VESTAX. Thanks for your support! And give 'em the Johnny Cash salute.

[guitardad]

Well it's fixed.

Since Op amps were blown apart on every pc board I shotgunned them. One audio issue was an highly resistive leg on a slide pot for CH1. So I took all the sliders apart and repaired them. CH2 was still weak audio, but I noticed it was missing bass. Had plenty of mids and highs.

I just swapped the boards from CH1 since it now worked to A/B Ch2. Pins 1 and 7 on a lot of IC's. I noted the waveforms main audio, bass, mid, treble filters, then reconnected the bad Ch 2 board. After examining the outs of many IC's ..eurerka!!! One had no LF out on pin 7. Checked around the circuit and all was fine. Replaced the replacement IC and success!!! Both boards worked! Main CH Faders, Crossfader were good (a slight bleed but all things considered not too bad).

Really sucks when new parts have issues. Take the good with the bad I suppose. 1 less unit in the landfill.

[Leo_Gnardo]

Well it's fixed. -- snip -- 1 less unit in the landfill.

Vestax will be soooooo disappointed. Send 'em the Cash salute anyway & "thanks for your support."

Having been to Japan 5 times, yes most of the natives are very polite. But . . . . there are a few who aren't. Maybe they are PO'd and still can't come to grips with the fact that honorable ancestors made a BIG MISTAKE. Heck we have similar in the USA, they still wave the Confederate flag.