Build Your Own Clone Message Board

Never built a pedal before and I'm having a hard time getting it working.
-Led works with both battery and adaptor
-bypass owrks
-volume works but compression does NOT work

I've been testing with a multimeter. Should both points read positive on everything? Some of the capacitor's(red) have a weak signal. Are they fried?

Should the 47* spots be filled if the pedal is for guitar not bass?

Any help would be greatly appreciated-I'm about 20 hrs. deep and no compression!

Pictures please. Could be any number of things.

Could you explain, "Should both points read positive on everything?"?

By "47*" do you mean the .047uf capacitors? If so then yes, they should have .047uf caps for guitar OR .1uf for bass.

Sorry for the delay...computer is being difficult
Could you explain, "Should both points read positive on everything?"?

Sorry to be so vague-I've never even used a multimeter. You test the board by having one end on the tip(black) and the other(red) on the capacitor, transistor,etc...) should every post on the board read positive on the multimeter?

Hopefully these pictures help

Can't post more than one at a time

In the 10n on the board, I have the O-L104. Should it be the O-L 103 possibly?

Where did everyone go? I did a little resoldering on the board and she works! Now I know what people on the forum are talking about when they mention the volume swell-this is normal? If so, I'm pretty sure she works.

With the negative terminal of the multimeter connected to circuit ground all voltages measured by connecting the positive terminal of the multimeter to points on the effect circuit will be positive. With the pedal powered from a 9V battery all measured voltages will be between 0 volts and + 9 and a bit volts. This is true of most, although not all, guitar effects.

The output pins 1 and 7 of the two halves of the op amp should be at half the battery voltage (about +4.5V). If they aren't check the divider R11 and R12. There should be about 4.5V at the junction of those 2 resistors.

The original aim of compressors was to control volume without it being obvious. However guitar effects compressors are usually pretty obvious. You will often hear a little blat at the start of the note before the compressor kicks in, it may seem to first squash the note then sound as though you are gradually rolling the volume knob up as the note decays. I believe the BYOC optical comp is one of the more smooth sounding compressors.

Thanks for the info! After a bit of playing around it is smooth. It's a little too late to be wailing on the Twin but tomorrow will be the true test.