Help please? Tonebender input voltage issues

[timmyo]

OK, Transferred the breadboard layout (NB it's PNP negative ground if that makes a difference) to the stripboard by basically following the circuit around the schematic again - there are probably much tidier ways of doing this circuit on stripboard, but this is at least electrically correct so for first time out, that'll do.

fired it up: nothing. Then the obligatory couple of hours fault-finding and re-soldering (variously I had a wrong-way-around electrolytic cap, a missing ground jumper, a shorted strip and a dry joint lol)

Then came the oddness: hooked it up to my I/O box to try out (not got the fittings for the final enclosure yet) and was getting a very thin, so quite right sound, which disappeared completely if the guitar vol rolled back even a little bit. Checked and rechecked everything MANY times, then at some point for no real reason I hooked up a battery instead of the external supply and it worked perfectly.

go back to external supply - odd behaviour.
The battery is putting out 8.89v the PSU is putting out 9.4v
When I hook the battery up the +V and Ground points on the board show the 8.89v.
When I hook the PSU up, the +V and Ground points show 1.65V (!?)

there is a sag control on my IO box - if I back it off to nothing and wind it up the voltage on the board increases fine up to about 7v, at this point if I un-sag it further it collapses back to 1.6 or so volts. I then have to sag it back low to be able to see anything higher as I turn it up again.

Is this because the PSU is putting out too much voltage and some component or other doesn't like it? I'm very confused.

In any case, on battery it works fine and is ready for boxing.

Somehow the circuit seems to have picked up more noise coming off the breadboard to the stripboard - hoping that resolves itself a bit when it goes inside a box.

If you're offended by messay layouts and bad soldering, look away now.

[timmyo]

ok hang on - I think it's just a dodgy connection on my sag control  
As you were.