My Duocast is almost really good!

[HamishR]

I've already built the single version of this pedal (Simulcast?) and that one works fine. But the Duocast is causing me an issue. It seems to work fine when the voltage switch is to one side or the other, but in the middle setting I get no sound until I switch it to the left or right setting. Switching back to the middle setting works briefly and them fizzles out like a badly biased transistor. No amount of strummage will reawaken it. I have to move the voltage switch again before it will work.

This happens in either channel. Everything else works just fine, and I'm actually really happy with it in the middle voltage setting which I think is to the right. But I would rather get everything working because it may be a sign of something more serious. I'm only really using it as a boost so not using a great deal of dirt from it. It makes a rather spectacular boost!

I have changed the LT1054 charge pump and that made no difference. Using a 1044 didn't make any difference except it added a whistle. No bells though. I've tried different Ge transistors - no change. All of the relevant electrolytic caps are rated at 50V. I didn't use any 120µF though as they wouldn't fit, so I used 100µF. I do have a big mutha of a 330µF in the correct place though.

No dry solders, no bridges. I can't work this one out. Any ideas?

 

[JamieJ]

I thought the switch was an ON/ON switch @HamishR ?

It swaps between 9 and 27v.

 

[HamishR]

Aha! It seems you are right! How could I have buggered that up? Maybe it's a 3-way in the smaller version?

Thanks Jamie - sorted. I also noticed that I used a 4K7 for one of the LEDs, but it works fine anyway. The LEDs I used are the ones around the switch which are supposed to use s 470R resistor.

So I'm swapping out a switch and a resistor. Something to do on a new years' day I guess. Thanks mate and happy new year!