Hello all, I am building Tommy III using 3pdt board. The problem is 3pdt switch works well to turn off and on the pedal but led is always on. Tried to find the problem but couldn't have any clue. Could it be the 3pdt switch? Could you please help me to solve it? Thanks in advance.
SOLVED Tommy III led problem, it is always on
- Thread starter ntuncer
- Start date
BurntFingers
Well-known member
It could be the switch, could be the power, could be the wiring, could be the soldering. Without pictures of the work done it's nigh on impossible to diagnose.
Post up some pics dude.
Post up some pics dude.
BurntFingers
Well-known member
...where's the led?
Also make sure you're not shorting out the backs of the pots on the PCB. Since there's no dust covers it helps to cover the back in electrical tape, or use a business card sandwiched between pot backs and pcb.
Also make sure you're not shorting out the backs of the pots on the PCB. Since there's no dust covers it helps to cover the back in electrical tape, or use a business card sandwiched between pot backs and pcb.
It sounds like the SW pad/wire is shorting to ground somewhere. If the LED cathode is always connected to ground it will always stay lit, no matter if the pedal is on or bypassed.
Can't see for sure, but check if the GND and SW pads/wires are shorting together. Check for frayed wires, solder bridges, right wires going to the right place, etc
Can't see for sure, but check if the GND and SW pads/wires are shorting together. Check for frayed wires, solder bridges, right wires going to the right place, etc
I checked again with clear mind. There is no sound when the pedal is off. And also Led is always on but when pedal engaged led's light is brighter. Could you please share the voltage value for the IC? I am open for all the ideas to diagnose it.
VREF: 4.88V
IC Voltage read:
1: 4.88v
2: 5.12v
3: 4.008v
4: 0v
8: 8.87v
6: 4.87v
6 4.88v
5: 4.87v
when I disconnect SW wire from the board, no light.
VREF: 4.88V
IC Voltage read:
1: 4.88v
2: 5.12v
3: 4.008v
4: 0v
8: 8.87v
6: 4.87v
6 4.88v
5: 4.87v
when I disconnect SW wire from the board, no light.
Last edited:
Similar threads
- Question