Lexicon PCM 80 help

A

alund

Well-known member
Recently purchased a used one off the forum: phenomenal sounds and no issues until about 4 weeks in noticed during play it would start a memory check (maybe it never really booted up fully-idk). Anyway I assumed there was a storm power surge as we live in west TN and it happens here-but I don’t typically play anything of a touchy nature during storms. Happened a few more times and shutting down then turning on fixed the issue. Now it just gets stuck in the boot up phase with the below message. No real message. No error. Tried the reset. Worked first time, shut it down again and rebooted to make sure…. Ehhhhhhh! Same. Ideas? Great unit when working. Cable weight when not 😕
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Before you go cleaning, check for leaking or bulging caps. You need to verify the rail voltages are within tolerance.

Also if you screw up one of those ICs, there’s little chance of saving the unit outside of buying another pcm for parts. Most are proprietary and haven’t been made in years.

I suggest looking into sending it in to a vintage restoration location that can refurbish it. If you don’t know what you’re doing in there then these are not units to learn on.
 
Bruce Egnater fixed one of my Lexicon MPX G2s which I was told was un- fixable (because of the error message displayed), but he reflowed the solder on one of the ICs and it works great, contact him on FB.
 
Glad to hear it's now working !

Could have been any one (or any combination) of the following:

The caps can hold a charge (when they should release it).

The caps could be failing (or failed)

There could be dust/debris in the sockets preventing a gas-tight seal between the IC legs and the sockets.

Could be a bad solder joint, which could have been resolved by flexing the circuit board.. but will probably come back at some point requiring you to re-flow solder.
 
So I have a show coming up… I guess the question is… should I chance it? Also. I don’t have one of the cards for storage and more sounds. Are they worth the value?
You know come to think of it, it only had a problem when I put the unit into the Fryette PS100 fx loop? Myasnikov Cii+ as the pre. Didn’t have a problem between the Soldano power amp and Myasnikov…. Coincidence?
 
alund said:
So I have a show coming up… I guess the question is… should I chance it? Also. I don’t have one of the cards for storage and more sounds. Are they worth the value?
You know come to think of it, it only had a problem when I put the unit into the Fryette PS100 fx loop? Myasnikov Cii+ as the pre. Didn’t have a problem between the Soldano power amp and Myasnikov…. Coincidence?
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If you need this gear to be "gig-worthy" I'd take it to a pro and have them re-cap it and re-flow any solder joints that look sketchy.
 
alund said:
So I have a show coming up… I guess the question is… should I chance it? Also. I don’t have one of the cards for storage and more sounds. Are they worth the value?
You know come to think of it, it only had a problem when I put the unit into the Fryette PS100 fx loop? Myasnikov Cii+ as the pre. Didn’t have a problem between the Soldano power amp and Myasnikov…. Coincidence?
Click to expand...
The cards are definitely worth it.

The 80 could use the dual FX or the phase mod cards. The 81 comes with the phase modulation already built in so it can only benefit from the dual FX cards. Both have the option of using the memory expansion cards to save more customized default settings but what’s the fun in that? lol
 
I only use my 81 for reverb, never dabbled in circular delays but I know Leon Todd has a video on the 80 or 81 showing how to do that. Your best bet is to go over to TGP and go search the massive lexicon pcm thread for more info.
 
glpg80 said:
I only use my 81 for reverb, never dabbled in circular delays but I know Leon Todd has a video on the 80 or 81 showing how to do that. Your best bet is to go over to TGP and go search the massive lexicon pcm thread for more info.
Click to expand...
Ahhh. TGP. Don’t think of that too much. Thanks.
 
PLX said:
You have to open up the unit and clean the circuit board, removing dust & debris. Use compressed air.

Unseat all IC's using an IC puller and anti-static wristband.

Reseat IC's and restart.
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If he uses a compressor and lives in Tennessee, you don't want to use a compressor that has water I'm the tank, due to the region's high humility.
Humidity can mess up circuits.
 
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