Barber Silver LTD - Please Help

Started by fenderislife, September 05, 2009, 01:01:46 PM

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fenderislife

Hi everybody,
I've just built a Barber Silver LTD.
It works, but Drive and Tone Knob have no effect on sound. It sounds like Level and Tone knobs are maxxed out to 10.
Volume pot and trimpots work. When i touch drive pot's lugs with my hands it shuts completely (rebegins to sound when i take them off)
I've tested the voltages, checked the boards, substituted the pots and the IC but didn't resolve the problem.
What's the problem? what can I do to solve?
Thank you!
IC: TL072
pin 1 4.35V
pin 2 4.52V
pin 3 4.31V
pin 4 0V
pin 5 8.90V
pin 6 4.55V
pin 7 4.52V
pin 8 4.01V
Didn't modify any value.

Here's the schematic
http://www.barberelectronics.com/images/barbersilverltd.jpg

This is the layout and pcb I used
http://www.madbeanpedals.com/builds/ltd/BarberLTD_rev1_TN.gif

Thank you!
Andrea - Italy

fenderislife

anyone who helps me in debugging, please?

chi_boy

#2
Can't say for sure, but I'm guessing someone will ask for more voltages.  Madbean's layout is already verified, so it is likely an error.  Can't help more, but I do have a Madbean ready to populate too.  Good luck!

This is a better link to the layout:

http://www.madbeanpedals.com/builds/ltd/BarberLTD_rev1.gif

"Great minds discuss ideas, average minds discuss events, small minds discuss people." — Admiral Hyman G. Rickover - 1900-1986

The Leftover PCB Page

fenderislife

i've already measured the voltages where on the schematics is written 4.5v and 9v and they are correct. Any other ideas?

chi_boy

"Great minds discuss ideas, average minds discuss events, small minds discuss people." — Admiral Hyman G. Rickover - 1900-1986

The Leftover PCB Page

fenderislife

already checked awvwrything in those posts...