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Transistors are pretty hardy unless they're reverse biased, I don't think any will have been harmed.

Yeah, upping that to 16V was a safe bet  Higher voltage caps would have both been more expensive and physically larger back then, probably why it was as low as could be gotten away with.

Yup, that sounds like old EHX electrolytics

Replace like for like, don't try and adjust values for the schematics, your unit is as intended. The schematic is purely for reference.

No, testing the resistors would be overkill, some unit component drift is part of its original sound, but a 5% drifted resistor isn't going to kill a unit (unless it's visibly black from burning out) unlike a dead capacitor. Very-very rarely they had a carbon composite resistor which can go brittle, that's about the only time I'd ever consider testing or replacing a resistor but I can't see any there.

This should be it https://github.com/zanepollard/SX-70-PickOff

If you can hook me up that would be amazing.

From time to time I dabble with cameras and I need a spare part 3D printed to repair one, would any of you kind people be willing to undertake such a task for moi?

Those other caps are ceramic, wouldn't ever suspect a mica cap and any way, easy to test, if it had an issue the 4047 clock wouldn't work.

I'd just leave the power caps as electrolytic personally, another 40 years of service life and keeps it fairly original.

Just replacing the electro and tantalum is all I'd worry about.

Well, you were definitely right about it having been worked on before, several new chips there.

I wonder if the same section might have failed again, if it has, an electrolytic/tantalum re-cap will be in order. There's not a lot of point keeping them original, their value has usually drifted horrendously over the years (some EHX I've repaired they've all been at 100% off tolerance) and all that'll happen is they'll eventually fail even if they haven't already so you're giving it a much longer potential life.

Stick all controls CW, no need for an input signal.

First things first, post a full set of voltages for every chip, you either need to trace it and correspond the IC numbers to the rust bucket or photo it and annotate the image.

Second, the 2N5088 & 5087 are probably original, they were interchanged with BC239 & 309 @ EHX regularly.

Third, don't assume it's been worked on, EHX did a lot of in house modifications for when particular parts were out of stock or circuit updates/modifications etc. and their soldering could be... less than desirable.

Fourth, pictures suit me best.

If you wish to go the shotgun route, replace all the CD chips in sockets i.e. 4047, 4066 etc. (the MN3007 will almost certainly be fine) as those are likely culprits and have no bearing on the 'sound' of the effect.

Oh and I don't know which attack decay schematic you have, but the main 'original' one on the internet is very wrong.

This sounds like a job for Scruffie

Only if he buys me flowers

I tried switching out the Xvive chip I got for a MN3207 which technically should still work, albeit not well.

Sorry to have to tell you, but you've killed or at the very least damaged that 3207 now.

A 3207 has inverse power and ground requirements and a maximum supply voltage of 12V (or is it 11?)... you have to account for that when swapping them.

No clock (1/2 supply on pin 2 & 6 of 3007 when working) = no BBD signal.

4013 and Q3-5 are where you have to dig.

I looked at the schematic for the FZ7 and it does have some similarities but I don't think it's close enough to call it a copy or variant

Here's a screenshot of the Pedalpcb schematic for the Ripped Speaker

Here is the signal chain as far as I can see:
Input > lpf > hard limiting diodes > buffer > single transistor "Fuzz" gain stage  > two transistor, biased "Rip" gain stage > tone stack (baxandall?) > Output

...not sure what the other transistor is doing in the power section, or is that part of the bias?

Opamp Buffer (LPF is just RF, diodes are op amp input protection) > 2 x LPB-1 style gain stages (basically a big muff, minus clipping on the 2nd stage) 3rd stage is another LPB-1 style stage with a Maestro FZ-1 style bias control, > Tilt Style EQ > Output.

Transistor in the power section is a buffer for the V.Ref, saving an op amp.

Okay, while I think 4066 should work to test, I do recall reading that they don't quite work the same in a switched resistor set ups so you'll eventually want to exchange them.

Fingers crossed that'll resolve your issue.

Okay, well, just a quick and dirty test, swap around IC10 & 11 and then see if the signal loss moves to IC3.

If so, probably a good idea to replace the (now) IC10 4016 chip.

Yeah, clock looks good, PWM output is a little tricky to see, but I think it's okay.

So can you audio probe in this sequence;

IC9 pin 10, IC3 pin 7, IC3 pin 1, TP-2, TP-3, Q3 emitter, IC2 pin 1, IC2 pin 7, TP5.

Let me know where you lose signal there.