Thing-A-Ma-Bob Troubleshooting

[jdiala]

Hello! So I tried out another 386 project. This one is supposed to be incredibly simple, but when I got it fired up, it makes all kinds of extra noise. Lots of extreme hum and not really gated regardless of the settings. It almost sounds like it might be picking up radio waves but its so distorted that I can't tell. I added the 100K volume pot as suggested in the website. It has the potential to sound like an awesome fuzz but I can't use it with all the extra noise. Any help in taming this pedal would be greatly appreciated.

Schematic is here: http://woodylaboratories.wordpress.com/2012/08/13/thing-a-ma-bob-atarinintendogated-fuzz/

[FUZZZZzzzz]

I've posted my original design here:
http://www.diystompboxes.com/smfforum/index.php?topic=84195.0

theres lots of info there

[FUZZZZzzzz]

I've posted my original design here:
http://www.diystompboxes.com/smfforum/index.php?topic=84195.0

theres lots of info there

allright.. have you cut all the traces (red boxes) did you use all the right value components? did you use the polarity on the caps?
how did you connect the volumepot?

unfortunately, even though there arent many  components.. mistakes are easy to make
can you post an image of your board?

[petey twofinger]

make sure you havent mixed up the hot / ground on the signal path ... like swapped the wires going to the jack ... i did that once (many many times )  , its not exactly quiet .

[jdiala]

So I went back in and I noticed that I had C1 connected to pin 3 of the IC. I corrected it but it's still pretty wild. I tried just pressing my hand on the back of the board and I managed to get it to work temporarily but I had to press a certain way and lost it after I moved. I also checked and double checked my ins and outs and everything seems to be in order.

The wires follow the schematic as far as I can tell. The wire with the shrink wrap has R1 tucked inside and leads to lug 3 of the fuzz pot. The wire between C2 and the IC is the wire coming from lug 2 of the fuzz pot. I should also mention that I didn't have a 10k linear pot on me (Tayda messed up my order and sent me 1k pots instead). Right now, I've got a 250k linear pot with a resistor between the two lugs being used on the fuzz pot which brings it down to about 9.6k according to my multimeter. Is this okay or would it be the culprit? The only other pot that I might be able to use right now is a 10k log pot. Would that be better for a temporary solution? The two extra wires up at the top right of the board go to the negative terminal of the power supply and to lug 3 of the volume pot. The black wire with the red burn mark is the 9V wire and the below that connects pin 5 of the IC to lug 1 of the volume pot. I also have the jumper from the ground strip on the board to pin 4 on the IC.

So here are the pictures of the board, both front and back.
Front - https://docs.google.com/file/d/0By_9D2hvXFK5UU5NU2lhNW1PbHM/edit?pli=1
Back - https://docs.google.com/file/d/0By_9D2hvXFK5VElGaXB0TU1pMTg/edit?pli=1

I was able to build a tremolo and a bluesbreaker clone on a pcb. I should be able to do this simple stripboard circuit!
Help? LOL!

P.S. I feel honoured to be the presence of the guy who invented this circuit. Thank you so much for helping me debug this!

[petey twofinger]

pressing on the board and then it work ... theres something ot right .

you reheated all the solder points ?

check it out under a bit of magnification .

[jdiala]

I have done that but I'll try again. It's only a few parts so I might just remove everything and start again. I'll let you know if it's still going crazy.

[jdiala]

I discovered that I didn't use the right resistor. So I redid the entire circuit, replaced the resister with the correct one and...



It spat out a high pitched squeal so loud I could hear it even with my amp turned all the way down.

So I unplugged everything and decided to go back to my desk and try again. But something told me to try again so I turned around and maybe try fiddling with the knobs. So I plugged it back into my amp and...



Silence. Not a single sound except for some white noise in the background.

These LM386 projects are driving me nuts! I might just shelve these and move on to my other projects, but part of me wants to just get these fixed and onto my pedal board. I'm not sure what else to do...