Hi everyone,
I got a new-old-stock Reverb 2 pedal kit. It comes with v1.2 parts (e.g. C10k pot and R7 = 15k). It comes with a v1.1 PCB (i.e R7 labeled as 10k).
Symptoms are the same whether on battery or 9V regulated wall wart.
Bypass feature works and sounds fine.
After switching, there's no signal, no LED.
I've a fair bit of experience with electronics, so I've started stripping it down to reduce complexity and isolate the problem, but no luck so far.
I removed the BTDR-2H.
I've taken off all the caps (in case of failed short caps)
I replaced the diode (1n4001 -> 1n4003 from the bits box)
I replaced the LED with a spare
I've removed the 5V reg and the opamps
I've reflowed every single solder joint
I've tried 2 different power input jacks
I've tried both battery and PSU
I've tried totally disconnecting PSU wires and bridging the "+" connectors to run solely off battery.
Basically I'm left with resistors, the stomp switch and the LED. And it still doesn't work!
I get 9V across "+" and "-" power terminals.
I get 9V across the 78L05's input pin and "-" terminal.
Something curious: when I measure voltage across 78L05 input pin and ground I see 9V (expected), but I also see 9V across the 78L05's middle pin (GND) and the "-" input terminal! I would expect the 78L05's middle pin to be tied to ground in order for it to function. Is this normal?
Pics:
Help!!! What should I check next?? Thanks in advance.