Great, got it working on UK voltage with the method described above. The colour knob was not operating properly (it would feedback uncontrolably on full) so I tweaked the trim pot a little. I think I’m going to get hold of a signal generator and sort out the rest of the trim pots using a long method I found on the internet.

Just another quick question. I’m rewiring it as true bypass (don’t always do this to pedals, but this is one pedal that does colour the tone a little in bypass mode). What is the purpose of the resistors R1, R18 and R19 in these two schematics:

Can I just leave these out when I rewire the switch?

Thanks

[Edit, pics were far too big to post]

Just had a look at the unit today. It’s a 2 prong plug and looks to all be in original condition, apart from the knobs. Am I correct in thinking if I want to wire up a 2.5 mm jack to the unit all I need to do is run the ground (negative) wire from the jack to where the single green wire connects from the transformer to the board, and wire the positive wire from the jack to where the two brown wires from the transformer connect to the board? Would there be any benefit using two wires as it is at the moment, or would one be sufficient?

Also, does the transformer output 24v ac or dc? I think I read somewhere that the transformer outputs 24 vac and it is rectified to 18(?) vdc on the board. Would it matter if the jack to the board is being fed 24 vdc and then this is being fed through the rectifier stage on the board? Would this stage need to be bypassed or does it not matter? Sorry, I have not had too detailed a look at the circuit layout yet.

Thanks in advance.

While we’re on the subject, I just rewired the 3pdt switch and it is all working very well. However, I get a slighy popping from when the switch is operated, when the LED pulls current when being turned on. There are two solutions:

1) Add a cap and reistor: http://www.muzique.com/lab/led.htm

2) Rewire so that it is always grounded http://www.dazatronyx.com/support/true-bypass-technique.pdf (bottom right)

Which would you say is the ‘proper’ way of doing it?

Cheers”

Thanks a lot for the reply. I’ll wire it all up and tell you how I got on.

Sorry, my mistake! I meant to say

‘I read somewhere that these Russians are postive ground. They were obviously wrong!’

For future reference, if a circuit is postive ground (chassis is postive) and the outer part of the socket is also postive, does it matter if they touch? In other words, do you only need to isolate the socket if the outer sleeve is a different polarity to the grounding in the case?

From my understanding it is postive ground to begin with. That is where my main worries come from. Is it a simple task to switch between psotive and negative ground for a pedal?

Thanks for the quick response!