Yamaha PM3000 Inserts Acting Up (Pics Added)

I've decided to post this in the Brewery because it's not really a Lab project.

A friend of mine has a Yamaha PM-3000 that was making crackling and popping noises at low gain. Once he cranked it, everything worked fine. My first hunch was dirty/failing inserts. This proved to be the problem.

I'd like to know what you'd recommend to clean them. I generally clean electrical connections with isoproyl alcohol (99%+), and usually avoid DeOxit products. This is a live console in a very smoky, rough environment.

Any advice/recommendations is appreciated.

PM 3Ks had a recall for faulty input level trimpots; check and make sure this isn't a problem. Another problem was that the epoxy dipped VCA chips would run hot and develop cracked / crystalized solder joints. As a matter of course I would re-solder these using lots of flux anytime I had a strip on the bench. Occasionally a preamp chip would go bad, but usually would be stone dead; no noise at all. De-oxit was a fine cleaner for faders and controls on these boards.

I remember that the gain swithes became occationally noisy. Maybe that´s a place to look at when you´re at it.

Memories are coming forward out of the cobwebs - The insert switches were another source of problems, they would tend to go intermittent and either need a good cleaning or replacement. I used to own 3 of these, so I put in my share of time on them. I still have the service manual here somewhere. It's the only schematic that I've seen that you needed an 8X8 foot wall to pin the schematic to for viewing; It was like a roadmap of the world.

I spent some time yesterday evening troubleshooting... the inserts jack are very intermittent and tempermental. I completed the insert loop with a 1/4" TRS held in place, and everything worked great. At this point, I don't think the pad/gain switches are faulty.

I had no success cleaning the jacks, so I took a couple of the insert PCBs and am going to replace the jacks. If you have a part number handy for the insert jacks, I'd appreciate it. Otherwise, I'm sure I can dig it up.

Thanks.

This may be BAD FORM, but I have been known to take a handfile that is rounded and give inserts or 1/4" jacks a quick rub. I had an old guitar that the jack went bad every month or so no matter how much I cleaned it. I did that and the dang thing worked flawlessly for years after.

The problem is more likely the tip / ring shorting contacts that can't be reached with a burnishing tool. One more reason why I think all consoles should use open frame Switchcraft 12 series jacks for 1/4 inch. These things last a hundred years. I haven't seen any other manufacturer build anything as good; not even Neutrik.

I desoldered a couple of the jacks last night. They were made by a Japanese company Hosiden, but I was unable to locate the part on their website. It says "L:9.0" on the jack. I also checked Mouser and Digikey for something similar, but no luck. Joe at JLM seems to use a similar jack for his DIs.

Anybody know where I can get this?

Thanks.

Yamaha USA should be able to supply them; they are pretty good at keeping parts available for the professional products.

They have 1000+ in Japan but we're looking 4-6 weeks of backorder. I wonder where Joe at JLM gets his L jacks.

Same here in the Netherlands, I ordered spare parts for my own
PM 3000 and had to wait quite a while, about a month, before they
delivered.
Still have check mine completely....

Good luck!!

PS Do you need copies of the huge diagram?

Best regards,

Willem.