Home Forums GuitarPCB Build Support 4 – Track Fuzz (solved) Reply To: 4 – Track Fuzz (solved)

#8583
Billy
Moderator

The next thing I would personally do Jeff is try to track down where it starts

Op amps will go into oscillation if they are being fed incorrect voltages as I said a few things could cause it dry solder joints, incorrect values etc  I’m not 100% a volt over VA, VB 4.5v would cause it that is why I suggested trying a battery to rule that out or a regulated 9v power supply

I would first of all use an audio probe and check audio going in at IC1A pin 3 where I wouldn’t think you’d get it then check pin 1 output where you may get it that at least will give you the area to look at

Some of your solder joints do look suspect

Where did you get the TL072 and what wattage is your soldering iron I also note that R2 and a few of your 10K resistors are 1/2 or 1 watt size R2 is in the IC1A feedback loop so it could be with its thicker legs it’s not making good contact with the pcb