lexicon model 200 & pcm60 need repair

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axisdreamer

Active member
Joined
Jun 26, 2005
Messages
25
Does anyone on here care to take a try at fixing these two units?

The pcm60 has a hiss sort of noise on the effected reveb out and its only there when a signal is being treated with the reverb.

The model 200
I was getting some numbers up on the diplay at first but couldn't seen to change them with hitting any of the progran number buttons.I tried turnning it off and re-seating the 4 v1.2 chips and now get no display at all when turned on.

Jim Fabiano is no longer working on Lex stuff so we're on our own I guess?
I would like to at least get one of these working because I'm getting ready to mix my new cd!

Anyone?

Thanks, Stace
 
[quote author="Jim Fabiano Website"]UPDATED: APRIL 02, 2008

AS OF APRIL 02, 2008, I REGRET TO TELL YOU THAT I HAVE CLOSED THE BUSINESS INDEFINATELY. AS I TRIED TO KEEP IT OPEN FOR THE PAST 6 MONTHS OR MORE AND WORKING A FULL TIME JOB THAT REQUIRES TRAVEL, I DON'T HAVE THE TIME, AVAILABILITY OR FINANCES TO CONTINUE.

I AM ALSO IN THE PROCESS OF RELOCATING WITHIN THE NEXT 3 MONTHS.

I AM AWARE THAT SOME OF MY CUSTOMERS HAVE SENT THEIR UNITS IN FOR REPAIR AND WILL HONOR IT BY REPAIRING IT OR RETURNING IT UNREPAIRED AT NO CHARGE.

THEREFORE, PLEASE DO NOT SEND ME UNITS FOR REPAIR.

PLEASE DO NOT CALL CENTRE MUSIC AS THEY ONLY RECEIVED AND SIGNED FOR YOUR UNITS AS A COURTISY. THEY HAVE NOTHING TO DO WITH MY BUSINESS AND HAVE NO INFORMATION ABOUT THE STATUS OF YOUR REPAIR.

I WILL CONTINUE TO PROCESS ALL SALES ORDERS BUT PLEASE ALLOW 2-3 WEEKS FOR DELIVERY.

OVERALL, I APOLOGIZE FOR ANY INCONVENIENCE THIS MAY HAVE CAUSED SOME OF YOU. ESPECIALLY THOSE WHO SENT THEIR UNITS IN FOR REPAIR SEVERAL MONTHS AGO.

Sincerely,

Jim Fabiano [/quote]

Well that's just terrific. I wish I would have known that before I spent $30 to ship him my PCM 80 over a month ago. If I would have know this I could have:

1. Used a ten dollar bill to roll a cone.
2. Used a ten dollar bill to wipe my ass.
3. Used a ten dollar bill to buy nudie mags.

At least it would have gone to some sort of use. :wink:

I can't blame the guy for moving on to better things in his life. It just sucks that there are no Lexicon gurus to take on his work. :cry:
 
I can probably fix them, if you don't mind shipping to Canada... unless one of the custom IC's are gone - that would only affect the PCM60. Possibly Jim could sell the chips? The 200 uses a discrete ALU which is almost always possible to repair. Usually it's the DRAM that goes bad on the PCM60's, though. If you can find someone locally that would be better for you.

I've been fixing quite a bit of Lexicon, Eventide, and Deltalabs gear the last little while and having good luck with them. Sometimes it takes a few weeks to get replacement parts, though.

The biggest risk, I think, to some of these older 'verbs is having the EPROM's go blank with age. If there are other lab members with EPROM burners and the same 'verb, we could get firmware images. The other risk is DRAM's. In some cases, a more modern replacement IC would be required.

-Dale
 
I fixed a PCM60 quite a while ago. it had cyclical noise in the output. I changed the DRAM. They are hard to find these days. I bought a few extra. they are somewhere in my shop.

What is wrong w/ your units and where are you located.
 
I'm located in Pa here in the states.

The pcm60 works but has a small hiss noise in the reverb tail.The units not noisy overall, it's just when signal is being mixed in with the reverb.

The model 200, I'm not sure what all is going on with it. I don't even get anything up on the number display when I turn it on and when I did I couldn't change the preset numbers. I didn't try running audio in and out of it yet.


Where are you located?

Thanks, Stace
 
PCM60: I'd look at the DRAM first, I'd guess one of the least significant bits.

200: The processor is probably not powering up, audio will probably not be able to go through the reverb. You may have a blown chip here, or possibly a partially erased EPROM chip. It is possible that an ESD hit blew up one or more chips in there. Another thing to check for is caps on the power supply. If the +5V supply is horrible-looking, the computer won't run. Check it for noise and voltage level. Careful not to short anything out so you don't blow something up. Most computers require 4.75 to 5.25V to run and a quiet supply. Glitches on the power supply will cause the logic to screw up.

Also, older computers (such as this one) are extremely sensitive to ESD. Those chips were all made before ESD protection was really understood. Be careful - you might want to have a proper ESD workbench area if you're digging in there.
 
Jim Fabiano stopped doing service. That is too bad.

He was very helpful to me one time when I had a 200 in that was doing exactly what yours was at first. Strange characters, and no response. He told me to check the backup battery voltage. It is a black encapsulated flat pack deal in about the mid right of the circuit board. Look around, you will find battery style markings on it ( +, - voltage, type, manufacturer, etc.) Measure the voltage between the + and - pins of the battery pack with the unit unplugged, and powered off. If it is below about 3.0V there is the problem. It will likely be completely dead. (less than 0.5V) Mine was. It needs to be replaced. If this is something you are comfortable with PM me, and we can work something out for the time and instructions, or you can send it to me, and I can do it, and recap it, if you like. The battery replacement is not drop in.

As far as reseating the chips, and now having it blank, I hope you used static precautions when you did so. (wrist grnd strap etc.) The best I can suggest is check the battery and hope for the best if it needs to be replaced.

As far as the PCM 60 I have no idea. I am more of an analogue tech. We got lucky with the 200.
 
So here we are a year later and Jim has not fixed or returned my PCM-80.  There's no number to reach him and the fucker doesn't return emails.  Anyone know how to reach this guy? 
 
My 200 has V1.3, same as the 200 of a friend. So in case of emergency we have the original Eproms. But I still don´t know if they are copyprotected..
 
Hello there!
Digging a burried-deep post... :)
I'm in the process of troubleshooting a Lexicon PCM60. I have very few experience with digital electronics...
My unit is fully working but has a lot of noise when reverb comes in the mix (the signal/noise ratio is nothing like what I have heard on online demos of the unit). The dry signal is OK though.
I've replaced the power supply electrolytics as a precaution to be sure my PSU rails are OK.
From what I've read above, the DRAM ICs are probably the culprit. How to check if this is the case before purchasing those kinda rare ICs? (I have a scope)
Thank you in advance for your advice!
 
There are four DRAM ICs in the PCM60, same label, actually they are MB81416 in my unit, and not IMS2620 as I thought it would be, but it seems to be the same component from different manufacturers.

I switched the DRAM ICs to see if it changed something about the noise, and actually it does! I think one of them (U23) is damaged as it gets noisier if I move it to IC18, and a little less noisy if I move it to U26...

Is it OK to replace this MB81416-12 with a MB81416-15 (That is to say 150ns instead of 120ns)? Would that fact that the latter is slower be a problem?
Thank you in advance!
 
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