FuzzDog kit - Ruby Cricket Amp - HELP!!

TTony

A few weeks ago, I put together the FuzzDog noisy cricket amp from one of their kits.  This one;
https://shop.pedalparts.co.uk/Ruby__Noisy_Cricket_Mini_Guitar_Amp_-_board-mounted_controls/p847124_13914413.aspx

All worked pretty well.

But, putting it all in a neat little box that I've been making over the past couple of days, I managed to pull off a couple of the (power) leads.  Poor soldering!  No biggie, soldered them back on .... and the thing howled.  Like a feedback howl.

I've just spent the morning disconnecting all the off-board wiring (so, in & out jack sockets, pots and mini-toggles, power connectors) and re-connecting it all.

Still howls.

Discconnected everything again, replace all the bits that I could, re-connect it all ...and still it howls.

The volume pot changes the frequency of the howl, but as soon as I connect anything to the input jack (and power the circuit), it howls. 

I'd just buy another but I'd really like to understand what's wrong and fix it.  Oh, and they're out of stock.

Any suggestions??

(Yes, I did change the battery for a nice new one, and checked that it worked in another ruby kit that I put together).

PeteC

possibly might be a short on the board somewhere perhaps - have you checked with a magnifier for fine hairs of solder bridging across contacts? or a solder blob touching something ? 

TTony

PeteC said:

possibly might be a short on the board somewhere perhaps - have you checked with a magnifier for fine hairs of solder bridging across contacts? or a solder blob touching something ? 

Thanks @PeteC - yes - but couldn't see anything.  It has to be something simple and obvious, but I can't see it for looking.  Calm head and fresh eyes tomorrow perhaps.

After a bit of over-lunch reflection, I've now cannibalised a few components from the howling board, and added them to the simpler board that I'd built previously which turns the simpler board into the slightly more complex one.

Simple board with added bits works fine, no howls, and I've put that into the little box that I've been building, so objective is sort-of accomplished.