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This arrived for repairing.

It's a late '60 Tone Bender by Sola Sound.
I redraw the schematic with actual values and wires color...

Fuzz control works reversed.
Transistors and diode are unsigned.

Enjoy
Schematic

cool bro, thanks for sharing

what's the actual board dimensions?

76.9 X 75.9 mm

Why couldn't you have received a Colorsound flanger for repair?

I'm working on the board routing and....I could use a few trace side shots!

more pics...

Thanks for nice pic!
Could you measure voltages Qc1, Qc2, Qc3, please?

kymar wrote:Thanks for nice pic!
Could you measure voltages Qc1, Qc2, Qc3, please?

this!

Can you read the pot codes? Probably early '72.

kymar wrote:Thanks for nice pic!
Could you measure voltages Qc1, Qc2, Qc3, please?

Q1:

C = -5.024 V
B = -1.300 V
E = -1.232 V

Q2:

C = -5.024 V
B = -1.232 V
E = -1.140 V

Q3:

C = -2.540 V
B = -0.071 V
E = 0 V

Electric Warrior wrote:Can you read the pot codes? Probably early '72.

On pot you find:

Radiohm 100K A D-74

I forgot

Battery = 9.70V

Updated schematic:
added transistors voltages, moved battery switch to output jack

Fender3D wrote:
On pot you find:

Radiohm 100K A D-74

Thank you! That would be D-71. By 1974 the pot codes were stamped into the top surface of the pots.

lol

1.2 corrected electros polarity

32uF is a funky value but I assume since it is just going from -VCC to ground, a 33uF will be okay or whatever works LOL

thanks!

Sure. Sola Sound mostly used 22µF or 25µF as a power filter cap for these in that particular era. They started out with 50µF, but whatever works..

Cool unit! Glad you were able to share the voltages. Q3 was definitely what I would have expected. Q1 and Q2 are slightly higher than I thought they would be on the collector. Then again it's still roughly half supply voltage.

I know these "top hat"-style transistors are normally not marked. Has anyone ever seen marked versions of them anywhere?

I've seen a couple of marked ones in Tone Benders, but never the same type twice.

That's what I love about this circuit, nice and forgiving of different transistor types.

EW, I'm actually working on a build right now using your MkIII layout. The one with the 680k/150k bias string...I think I've got just the right gains/leakages in my stash of no-name germaniums. We'll see I guess!

Good luck! Trying different types in this circuit sure pays off! Q3 is quite sensitive to leakage. Great for shaping the tone. And I found that transistors wired up as a diode sound different from the germanium diodes I have. Worth a try!

I don't think leakage is that bad in mk3. I kind of like it if it leaks. I often fake leakage setting resistor or resistor in series with pot between C and B