Sunking II no Output when the Output Jack is connected

[theleftfoot]

Hi Guys,

I bought the Sunking II a long time ago and had some time to build this pedal. The Build went well.
At the end of the build i test the pedal always with the oscilloscope. the signal worked on the output tip...

then i went to my room hooked the pedal up and nothing came out! no guitar signal in the bypass or in the activated state. when the pedal is on i can turn the knobs and i hear the changes, but no guitar signal...back in the test room, i hooked my osci on and connected my cab on. after that i controlled the output and i saw that the signal was grounded!

i investigated the pedal a couple of hours, but i didn't find the problem...can you guys help me out? would be great!

the pots and the jacks are not isolated from the chassis...

thanks in advance raffa

[jimilee]

It's time for an audio probe.


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[madbean]

Yeah, you need to audio probe the following points:
IC1A pins 1 and 7 (set the gain halfway up)
IC2a pins 1 and 7

That should give you a clue as to where the signal is getting lost.

[m-Kresol]

I'm not sure, because it's hard to see, but please check the wiring on your input jack. It's possible that you hooked up the tip contact of the jack to the ring pad on the pcb (white wire). use a continuity tester if you're not sure which lug goes where on the jack

[theleftfoot]

Thanks guys for the inputs...! 

will report!

cheers Raffa

[theleftfoot]

hi, i've done the test...
when the output jack is pullged in, bypassed, the signal lost after R27 560R.

but as i sad, when nothing is plugged in the output the signal in bypass and switched on is here!

mhh...

raffa 

[theleftfoot]

Good Morning,

Can some one have a Voltage Chart? would be great! thanks raffa

[m-Kresol]

hi, i've done the test...
when the output jack is pullged in, bypassed, the signal lost after R27 560R.

but as i sad, when nothing is plugged in the output the signal in bypass and switched on is here!

mhh...

raffa

is it possible that the tip of the jack contacts with something on the board? there's not too much space there. Have you tried to use a different jack or cable? it's unlikely, but something could be faulty there.

[Willybomb]

is it possible that the tip of the jack contacts with something on the board?

The jack on the right hand side looks really close, but I'm going to put money on the actual tip of the cable is grounding on the board, specifically the pot lug solder joints.

[jimilee]

Or a bum
jack


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[theleftfoot]

cheers guys,

i kicked everthing of the inhousing and will do a new offboard wiring with new alpha pots...

will report! thanks for your answers...

raffa