CE-2 keeps turning itself off - help?

[jubjub]

Greetings my treasured stomp box brains trust.
I bought a CE-2 off ebay. Sounds great but after it's been plugged in for a long time it turns itself off. To be specific, the audio simply stops comming out as if it were dead, but the light remains on. You have to turn it off and then turn it back on again to get it going. Of course it only ever happens at a gig and I can rarely duplicate it at home. When it works it sounds great, but it's realy starting to anoy me that I can't rely on it live. Any thoughts on what it might be?

[george]

Greetings my treasured stomp box brains trust.
I bought a CE-2 off ebay. Sounds great but after it's been plugged in for a long time it turns itself off. To be specific, the audio simply stops comming out as if it were dead, but the light remains on. You have to turn it off and then turn it back on again to get it going. Of course it only ever happens at a gig and I can rarely duplicate it at home. When it works it sounds great, but it's realy starting to anoy me that I can't rely on it live. Any thoughts on what it might be?

old electrolytic caps?  I know there's one or two in the signal path - if you're pedals over 10 years old they may be wearing out ... hth

[jubjub]

Hi George. I've actualy had the pedal Keeley modded and I've sent it back to them and they say they can't find anything wrong with it. I believe they use the best quality components and I have some of their other stuff which is great so I'm inclined to believe it's something they haven't changed, and they replace all the caps. Would an electrolytic do that if it wasn't working properly?

[jubjub]

I'm looking at the caps c15, c16 and c17 on the schematic because Ican only think it's something happening on the out put, but then why when I stomp it to bypass and then stomp it again does it sort itself out, could it be the switch? but why would the light stay on and no sound comes out. Any suggestions would be appreciated. The schematic is up the top if you want to have a look. Just need a point in any direction to start me thinking

[george]

I'm looking at the caps c15, c16 and c17 on the schematic because Ican only think it's something happening on the out put, but then why when I stomp it to bypass and then stomp it again does it sort itself out, could it be the switch? but why would the light stay on and no sound comes out. Any suggestions would be appreciated. The schematic is up the top if you want to have a look. Just need a point in any direction to start me thinking

I wouldn't think it was the switch, because you're losing audio completely. right?  If it was the switch you'd get something even if only dry sound.

If c15 or c16 were shorted or open circuit you'd still get some output even if only very quiet.  C17 going open circuit would be bad.

Anyway was your CE-2 was working OK before it was modded by Keeley? if it does it kinda points to the op-amp they put in as well as anything else they changed - I'd personally be dissatisfied if they did anything less than replace *everything* they changed - you paid them enough money, this should be the least they do, after all the guy's supposed to be a qualified EE.

[jubjub]

I bought the ce-2 from ebay and had they guy post it direct to keeley, so I don't know if this problem was there before. I must say that the keeley guys have been very helpfull but they could find nothing wrong with it, and even I find it difficult to reproduce the problem. you've got to leave it on for like 2 hours and even then it only does it some of the time. The only way to gaurantee that you'll hear the fault is to make sure I'm going to use it in a song. From looking at the schem, the only other thing that looks like an obvious area is ic1 which looks like a dual op-amp. I might rtry and find a replacement and see if it helps. What do you think?

[george]

This would be fairly easy to do, because one of the mods is to replace the op-amp, also it's a good thing to try because all the audio goes through it.  You could probably sub in just about anything in there, LM358, TL072, NE5332.  SmallBear even has REALLY cheap JRC4558Ds ...

If that doesn't work, try send out an SOS to a guru like Mark Hammer ... I'm getting in over my head!

best of luck

[jubjub]

Thanks george. I'll find a good op amp and let uou know how I get on.
Have a great day.

[george]

you too man ... whenever day is in your part of the world - lol!

Another thing that comes to mind might be intermittent short circuits - I bought this beat old CE-2 off ebay, a lot of the wire connections were broken, but I could see from the photos the PCB seemed to be good.  

When I was inspecting it,  it  looked to me as if someone had been trying to repair it but totally got the shits and ripped out the wires (I know the feeling - I've been to the land of total frustration myself).

So I patched back together and it seemed to work pretty good until I screwed the bottom back on and it just cut out.  I opened it back up, figured a lug on the input jack was possibly shorting out on of one of the components.  I rotated it a bit and the problem was fixed.

Another thing is if it is REALLY old (Jap black label) it will only have a tiny pad of foam on the bottom of the PCB to prevent it shorting out on the base plate - It might be worth cutting up a bit of stiff plastic to put between the PCB and the lid like the later boss pedals.

just a few more $0.02s ....