SOLVED Chaos Machine trouble

[proffbass]

Hi,

I am unable to get my latest chaos machine build to work.

I am very new to pedal building but have managed to get 5 pedals working so far.

I have traced the signal from the input through R1 and 2 through to leg 3 of the TL072. Once it enters this Bermuda triangle, the signal vanishes without a trace.

I have tried different TL072 chips and the problem persists.

I am using IC sockets and have checked the continuity which all checks out with no cross contamination of the signal. The legs of the IC are connecting well to the socket.

I don't know what to try next.

Any suggestions?

 

[hamerfan]

Can you post the voltage at every IC. Legs 1 to 8, to ground?

 

[Nic]

Bottom right pot middle lug looks like it's not soldered. Might not solve the problem but ...

 

[proffbass]

Great call.
They

Can you post the voltage at every IC. Legs 1 to 8, to ground?

Great call.
Thanks so much.
They were all 0.
Turns out I was trying to fire the PCB from the output ports to the 3PDT.
All sorted.
I'm really pleased to learn a new diagnostic test.
Many thanks.

 

[proffbass]

Bottom right pot middle lug looks like it's not soldered. Might not solve the problem but ...

Thanks Nic.
I soldered the pots to the other side of the PCB. I had some temporary pots on there originally and soldered them goofy foot so I could remove them more easily.
Thanks again
Much appreciated.