Is my Boneyard fried?

[CK1]

Hi all,

Those on here who know me will know that I'm more of a player than a pedal builder, though I've become at least reasonably competent at building over the past few years.  However, I recently ran into an issue that I don't know how to trouble-shoot, so I'm looking for a more knowledgeable member to point me in the right direction.

I have one of the old style Boneyard pedals (3 stomp switches), and while I was swapping some pedals on and off my new pedalboard last week, it all of a sudden stopped working correctly.  I've had it for a couple years, and have used it regularly with no issues, so this is a surprise.  It makes a hideous hum sound when plugged in, and won't allow any guitar through at all.  When I touch both the input and output cable, a good portion of the hum dies down and some small amount of guitar signal passes through, though it sounds awful.  All the LEDs continue to work, also.

I'm assuming one of my two ICs is fried, though I don't know how to test that besides swapping in new ones (which I don't currently have, and must order).  I do have some of the other components socketed, so I made sure to re-seat everything, but to no avail.  Any ideas for a novice trouble-shooter?

[mattlee0037]

Maybe a signal or ground wire came loose? It sounds too random and unpower related to have fried

[CK1]

That was my thought too, but I couldn't find a problem with ANYTHING internally.  I haven't opened it up to try it again since the very first time it did that, so I'll give it another go this weekend and see what I can find.  Thanks!

[mattlee0037]

Maybe grab some voltages and continuity on all grounds?

[CK1]

Aaaaaand now it's working normally again.  WTF!?!

Hooked it up for the first time since the initial incident, just to try to troubleshoot with the "sound on" as it were, and it worked perfectly fine immediately.  This is SUPER strange, because it wasn't even moved off the board or anything since then.  No explanation.  Can't complain, exactly, since it saves me time and money to have it working again, but it still freaks me out a little that there was an incident at all.  Anyway, thanks for the suggestions, and I'll update here if it ever does it again.

[billstein]

Just a thought. I would check the wires in the jacks and the DC plug. Perhaps plugging guitar cords and power in moved a short just enough to reconnect for now.

[mattlee0037]

Yeah, makes me suspect the board or power is shorting inside the enclosure.

[pryde]

Hum is likely a simple grounding issue. Are the input/output jacks properly tight? Do you have the output jack grounded just to the chassis or also wired to ground?

Check every ground connection for continuity. Poke and prod all ground connections with the pedal on and listen for intermittent connections.

Also possible the 3PDT stomp is failing (if standard blue ones and heavy use over last couple years)

That's where I would start

[CK1]

Thanks for the ideas, guys 

I hate to pull it apart again, now that it's working correctly.  But I REALLY don't want it doing that at a gig, so I probably will anyway.  Appreciate all the input.

[wgc]

Check for loose pots, I've had one spin and ground out my signal intermittently