Electro Harmonix Guitar Pedal, not fully functional

[Ollie Elmes]

No problem... or any particular rush for that matter! Might be a good xmas break project for me if possible.

 

[c_mitra]

If you have some isopropyl alcohol (it is very cheap solvent; acetone can also be used), use an old toothbrush and scrub the solder side of the board gently. Use a multimeter and see if any of the traces are broken. Many are very thin traces and only covered with solder in a patchy way. Good or bad, it may be wise to replace the electrolytic capacitors (because I too have seen these transistors in my younger days) but note down the polarity before you remove them (anyway, these photos can be of help).

 

[betwixt]

I found lots of MC1458s but only one TL084, you are welcome to them. I haven't got your address to send them to. If you use the 'Send me email' (below the navigation buttons) on www.atv-projects.com and tell me your address I will drop them in the post.

Brian.

 

[Ollie Elmes]

Thanks Brian, e-mail sent.
@c_mitra Will lens cleaning alcohol do the job? Didn't see any photos on your last post. Were there supposed to be?

 

[Mattylad]

If you google zipper pedal schematic and look at the images there are plenty to choose from.

 

[c_mitra]

Will lens cleaning alcohol do the job? Didn't see any photos on your last post. Were there supposed to be?

No, I did not attach any photos. Most organic solvents can be used to clean a PCB: common alcohol (ethanol) or isopropyl alcohol (not useful for drinking) are widely used for PCB cleaning. It dissolves the resin flux and the oxidation product (the black smudge). Acetone is also available as common nail-polish remover. You can also ask local school or college lab for a small amount. They are very cheap. You can also use MEK (ethyl-methyl ketone; 2 butanone). You will need about 4-5 ml. The toothbrush is for gentle scrubbing, to remove stubborn oxidation products. With time, they have become more corrosive and also permanent.

Lens cleaning alcohol will not do; it is a very dilute alcohol and mostly water. It has very poor dissolving power.