While I was calibrating my pedal, I am unable to get a reading on TP 1 and TP 2. I was able to get tp 3+4 and tp 5+6 calibrated. Any Ideas on where i should start trouble shooting?
On those test points you are measuring the LDR’s resistance with the LED on, so if you have no reading it could mean that the LED is not on, which would make the LDR’s resistance very high (practically open). So make sure your LED is actually on. Measure the voltage across it with the depth knob fully counter clockwise (it should have around 1.8v dropped across it…compare it to the LOW side LED). Make sure it’s installed correctly. (When it’s off) Use your multimeter diode checker to test if it has the same reading as the LOW side led (make sure you measure both LEDs the same way…red on square pad, black on the round pad). Make sure all the solder joints are solid and there are no opens or shorts anywhere in that circuit.
Let me know what you find.
-Brach
So I just reflowed the solder connections on the led, and was able to get a propper reading. I got everything calibrated and soldered the jumpers together, but when I plugged the pedal in to test, all I got was an oscilating noise and a very faint guitar signal. Adjusting the controls effected the oscilations, and the noise happened whether the pedal was engaged or not. Sorry to take up your time, any input is greatly appreciated.
This sounds like there is a bad connection in the signal path somewhere…possibly a short or an open somewhere. Judging from the fact that reflowing some solder joints fixed the testpoint readings, it seems likely that you probably have some other bad solder joints somewhere. I’d very carefully re-flow all the joints on the board, particularly in the signal path. Take your time with this because pads can easily get bridged.
Good luck.
-Brach
Thanks Brach! I reflowed everything and got it in working order. Thanks so much for your help.
One last problem though. The pedal is stuck on. I’ve reflowed the foothswitch connections as well as the relay, and I can’t get it to disengage. I definetly knicked the relay with my iron, and damaged one of the corners. Would that be the source of the problem. The damage looks to be only structural, but I don’t know how sensitive the relays are.
Sorry for all the questions, this is the first pedal I’ve ever built from a kit.
And again, thank you. You have been so helpful and patient.
I’m glad to hear that it is now working.
This new problem of staying on sounds like another solder issue. I’m pretty sure just nicking the plastic with your iron wouldn’t damage the relay, unless you can see metal parts in there.
I’m assuming that the bypass LED stays on too….is this true?
…if so, you need to very closely check the solder joints around the switch (on both sides of the board). Use your continuity tester to make sure the square pad of the bypass switch is not connected to ground when the switch is not pressed (it should be connected to ground when it is pressed).
Let me know what you find.
Good luck.
-Brach