SEEKING SCHEMATICS/HELP: Electro Harmonix / Sovtek SMALL STONE (Russian)

[lilsugar]

Does anyone have schematics for the Russian Small Stone?

It has 4 chips:
CA3094E
H9540

And 1 chip:
CA3094E
H9536

It has been in my project pile for 1.5 years. Time to finish a few projects! LOL

[Jazz P Bass]

You may have a rough time finding the CA3094 IC.
Schematic Link: The Free Information Society - Electro Harmonix Small Stone Phaser Electronic Circuit Schematic
Google Images: http://www.google.com/search?q=small...w=1280&bih=630

[J M Fahey]

I gues it´s just a traditional Small Stone which can be searched and found.
Those 5 chips are all the same CA3094E , the second line is only a date code (and they are very close, within 4 weeks).

[doctor]

I gues it´s just a traditional Small Stone which can be searched and found.
Those 5 chips are all the same CA3094E , the second line is only a date code (and they are very close, within 4 weeks).

Here is the genuine schematic

[Mark Hammer]

Are you trying to repair one or build one?

[lilsugar]

Hello Mark!
I am trying to repair one.
I am a novice tech, excellent at soldering though, but not at troubleshooting and understanding/reading schematics. Here are some photos:

Electronics Project Pile pictures by Little_Resistor - Photobucket

I have added a new housing and LED. There are two wires that need to be soldered in 'somewhere', probably the 9v power input (missing) or the LED or both. I have not plugged it in to an amp yet (been in the pile for AWHILE) Some of the photos have descriptions too. There's also a white ground cable that needs to get attached to something inside... (?) as well as 3 leads that were clipped off the circuit board (hmmm)

I bought this on eBay as a broken non-working pedal thinking foolishly I could fix it, but here I am tryin' at it again!
Mary

[Mark Hammer]

There are some extremely worthwhile mods that can be done to the average Small Stone that will vastly increase its usability. Interested?

[lilsugar]

Definately interested in getting this pedal up and running. I'd like to get it to work before mods though, but let me know... What kind of mods?!?

[Mark Hammer]

Somethine like these: frankenstone

[sweatyk]

Here is the genuine schematic

I know this is an old thread but I'm searching for the same schematic. The PDF link posted here was blank. Anyone have one to share?

[nosaj]

I know this is an old thread but I'm searching for the same schematic. The PDF link posted here was blank. Anyone have one to share?

Contact EH they will email you what you want.

Thanks,
nosaj

[Jazz P Bass]

Here is a repost of the file:

[sweatyk]

Thanks Jazz. This one has the CA3094E chips in it. Someone has been into this pedal before. 2 wires were disconnected and taped off. One was coming from the LED. When I connected them the LED would stay lit constantly if the cables were plugged in. I guess to keep from draining the battery they did that. It looks like the stomp switch was replaced at one time and they probably have something out of place.

[Jazz P Bass]

Sounds like they used the wrong switch.

It appears to be a 3PDT in the schematic.

3PDT Stomp Switch | stewmac.com

[sweatyk]

Sounds like they used the wrong switch.

It appears to be a 3PDT in the schematic.

3PDT Stomp Switch | stewmac.com

Jazz it is a Fulltone 3pdt switch so it is correct. I believe the last hands in here did not reconnect the LED to the switch. Other than that the pedal functions. Hooking these 2 wires back into the switch should resolve that. It would take me a while if I tried to rewire the entire switch if it needed it. This is the version 1 of the Russian made pedal in which the PCB has no markings on it. Without those markings my schematic skills will be challenged and take me a while to wrap my head around it. Not impossible just time consuming for me. It's just not something I do on a daily basis. I will chime back in after I have had some time to work with it.