ground loop or something broken?

[celicaturbo]

hi everyone
i'm building an overdrive and the breadboards prototype work perfectly, now i want to make this definitive but i have some problem.
when i switch to ON i hear mostly the 60Hz of the supply and a few signal from guitar.
is a problem of ground or i have burned some components? (the circuit is on a pcb breadboard )
thanks all

[bluebunny]

Welcome to DIYSB!  Check out the sticky "DEBUGGING" thread at the top of this forum.  Follow the guidance in that thread and someone will be along shortly to help get your overdrive working.   

[antonis]

I'm not familiarized with the term "PCB Breadboard" but if you mean that you have the whole circuit populated and working on a breadboard, then your hum problem is rather common...

Try to cover the whole circuit with a grounded aluminum foil or - even better - place a RF filter to the power supply..

(and of course, follow bluebunny's suggestion..)

[celicaturbo]

sorry i have a little problem with the translation of some terms....the circuit in the bradboard works.
i have build the same circuit in a perfboard in a metal enclosure and this dont work.
the sound is covered with the supply noise

[canman]

Try a different power supply maybe?  I can't tell...does it produce the same sound as it did on the breadboard, or are you ONLY getting hum?  If just hum, check your switching/in/out jacks.

[bluebunny]

Test it with a battery in order to eliminate any PSU-borne noise issue.

[GibsonGM]

If it worked on the breadboard...and doesn't work after soldering and putting in an enclosure...then the most likely problems are:

1) a mistake when you soldered it together
2) a missing or broken connection to ground somewhere.

I always wire up my builds outside the enclosure first (with jumpers), to make sure they work.    Then I put them inside and permanently attach jacks, power jack, battery snap etc.  Any problems that come up can then be traced to something that happened when I installed it.    A missing or bad ground connection at an input or output jack, for example, can create AWFUL noise.    There should only be a few of those connections that need checking (3 or so?). 

If it still makes this noise when powered with a battery, I think you should remove it from the enclosure and look a bit closer.  A component touching the enclosure, or one that was bent upon installation and now touching something it shouldn't, are very common problems, too!