Need parts layout for EHX Micro-Synth

[Mark Hammer]

I have an EHX Guitar Micro-Synth on the repair bench. I have pretty well all the schematics I need for it, but there are ONE HELLUVA LOTTA CHIPS ON THE BOARD and none of them are identified by any legending. I could really use a component layout map or drawing of some kind so I could probe in the relevant places.

For now, it doesn't trigger or produce any sound other than the straight guitar signal. The filter "works" but doesn't sweep. Resonance works and both Start and Stop Freq controls will change the filter setting.

It's the first issue, or close to it, using the 5554 dual regulator, with no power-on indicator LED. Has a pale green PCB. If you could direct me to a legended pic or layout drawing, that would be terrific.

Thanks

[nosaj]

I have an EHX Guitar Micro-Synth on the repair bench. I have pretty well all the schematics I need for it, but there are ONE HELLUVA LOTTA CHIPS ON THE BOARD and none of them are identified by any legending. I could really use a component layout map or drawing of some kind so I could probe in the relevant places.

For now, it doesn't trigger or produce any sound other than the straight guitar signal. The filter "works" but doesn't sweep. Resonance works and both Start and Stop Freq controls will change the filter setting.

It's the first issue, or close to it, using the 5554 dual regulator, with no power-on indicator LED. Has a pale green PCB. If you could direct me to a legended pic or layout drawing, that would be terrific.

Thanks

If EHX has it they've always been more than helpful to me at least.. and your a big name when it comes to pedals too.

nosaj

[Mark Hammer]

I don't know about "big name", but I'll give them a try. I was hoping there might be something posted that a Google image search didn't locate.

Perhaps Enzo has something tucked away.

[nosaj]

I don't know about "big name", but I'll give them a try. I was hoping there might be something posted that a Google image search didn't locate.

Perhaps Enzo has something tucked away.

Hey your published and that's a big deal
I could find nothing of which you are looking for. Dumb question does the Footswitch work?
I have one it's a big black one in aluminum housing uses a 24vdc plug

nosaj

[Mark Hammer]

The footswitch does work, though I don't get bypass, only clean signal in synth mode. This one is a lot earlier than yours. It's big and black but uses the onboard transformer.

[nosaj]

The footswitch does work, though I don't get bypass, only clean signal in synth mode. This one is a lot earlier than yours. It's big and black but uses the onboard transformer.

Best I could do are these Factory schematics but no layouts.
https://sites.google.com/site/electr...ive/schematics
nosaj

[Enzo]

I am not in good shape right now, but my contact with Mike Matthews was all in the very early days. Low serial #Sovtek Amps, and the original Big Muff pedals made of Russian military parts. No layouts of digital stuff. But call them, they have tried to be helpful before. You are certainly a way bigger name than I am.

[Mark Hammer]

Note sent. I doubt that my verbosity on forums holds any sway with the people at the other end of tech-support in-boxes, but they've been responsive in past interactions, so I'm hoping for a repeat performance. Whether their archives are as fulsome as their desire to help may be a whole other matter.

[Jazz P Bass]

I am not in good shape right now.

Wishing you well, Enzo!!!

[Mark Hammer]

My good wishes for best health as well.

As it turned out, the right honourable Stephen Giles, who worked for EHX in Great Britain many years back, posted a scan of a drawing he had made years back, in response to my request, that labels all the chips corresponding to the same pedal issue. I think that may be enough to do the requisite detective work. Someone also posted a link to a site by Snarling Dogs co-founder Richard Excellente, where he describes his various roles within EHX over the years, including co-designing the Micro-Synth with David Cockerell. Very interesting reading.

https://captain6string.blogspot.com/

[nosaj]

My good wishes for best health as well.

As it turned out, the right honourable Stephen Giles, who worked for EHX in Great Britain many years back, posted a scan of a drawing he had made years back, in response to my request, that labels all the chips corresponding to the same pedal issue. I think that may be enough to do the requisite detective work. Someone also posted a link to a site by Snarling Dogs co-founder Richard Excellente, where he describes his various roles within EHX over the years, including co-designing the Micro-Synth with David Cockerell. Very interesting reading.

https://captain6string.blogspot.com/

Please share the scan of the drawing please.......

nosaj


Somebody ask Wenzo to give Enzo the good ole Enzo whack...that should straighten him out.....

[Mark Hammer]

Here you go.

[J M Fahey]

I am not in good shape right now, ....

Ouch!!!
Reached here searching for your latest post, since I was missing your great contributions after a couple days.
Get well

[Mark Hammer]

Fixed. All voices working again. The bridge rectifier was fried, and 5 dual op-amps were also fried when whatever happened, happened.