A little help with disaster transport jr please

[whomeno]

the blue cap was a 2.2nf changed it to a 22nf.
probed have tone at R11 & R13 connection, but nothing at R13 and pin 16
I built another board, it dose the same thing

[anotherjim]

pin16 is an opamp "virtual ground". You shouldn't expect to hear anything on it. Pin15 is the audio going into the delay, you should hear something on that.

[whomeno]

ok.  probed again
at connection R13 10K and R12 47K got good tone
AT R12 47K and pin 15 no tone.

[whomeno]

I don't know whats going on with this board, but I just built another board from a different layout, used the same ic's and it worked the first time.
Thanks for ALL the HELP.

[duck_arse]

the blue cap was a 2.2nf changed it to a 22nf.
probed have tone at R11 & R13 connection, but nothing at R13 and pin 16
I built another board, it dose the same thing

I have some questions. this new layout [link to, please?], what value cap did it call for at "C22", 2n2? and what value did you fit? I'm not real good with opamp filters, but a general rule of filters is that you can't replace a cap with one 10 times bigger and expect the same performance - and those MFB filters are picky about values. one of the gurus might elucidate for us.

if I might be so bold as to suggest going back to the faulty board and removing the 22nF and replacing with say a pair of 1nF in parallel, just tacked on to test, and see what happens. you might end up with two working boards for the price of one.

[whomeno]

duck_arse

Here is the last one i used. it seems all values are the same, just the board is a little bigger.