Ground hum (I think?) problem on a DIY OD pedal rehousing

[LonePhantom]

Hi there all. I'm a newbie to the effects pedal modifying and building world. I have done a few projects now modifying a few of my Boss pedals with some success.

My latest foray into the modifying world has been to modify a cheap Daphon E20OD Overdrive pedal (pretty much a Boss SD-1 clone), and then rehouse it in a new enclosure.

I finished my circuit changing mods successfully (add a switch to change clipping modes between symmetrical and asymmetrical, higher quality capacitors where needed, tonal changes with resistors and caps, etc). Pedal was working nicely, and getting the tones I was after.

I bought myself an aluminium enclosure, drilled it, etc, and installed my PCB and controls, etc. When I plug it into my guitar and amp all I get is a hum. No sound from the guitar at all. I thought it might be a grounding issue. In the stock enclosure the PCB is screwed onto the enclosure with a plastic washer. Would this be to ground/earth it?

I believe I have tested all points on the PCB with a continuity meter on my multimeter, and all of that seems to be fine.

I wired up what I think is the sleeve of the jack (the lug closest to the threaded lead insert?) and drilled a spot for a small bolt and nut to hold a wire to to the enclosure, but still get the hum. I've tried both jacks, and same result. I'ev posted an image of what I have. I hope it's clear enough to make out.

Does anyone have any ideas regarding this? Have I used the wrong lug on the jacks, or not used the correct part to ground to the enclosure? Anything else that might be wrong?

.

Thanks in advance

[MikeH]

In the stock enclosure the PCB is screwed onto the enclosure with a plastic washer. Would this be to ground/earth it?

Yes- It's possible that is your problem.  I'd make sure that that is connected to the sleeves of both jacks as well as the negative terminal on your DC jack

[LonePhantom]

Thanks for your quick response.

So should I use the point on the PCB where it was screwed on to the stock enclosure, or do as I have done to one jack to both jacks?

Or could I use a nut and bolt with a wire and put it on the PCB hole, and connect the other end of the wire to the ground point I have made on the side of the enclosure (the point at the top of my pic)?

[MikeH]

Not sure- I'm kind of losing you there.  Just make sure the ground trace on your pcb, the sleeves on both jacks, and you negative power supply connection are all connected.  If the pcb was grounded to the enclose via a screw, you need to recreate that connection with a wire or something.

[LonePhantom]

Thanks Mike, I'll see how I go.