Newbie pnp switch help

[helos]

Hi guys, I'm having an issue with a switching circuit that I'm using to bypass the fx... The transistor is 2N3906 and it's wired so that when the base is grounded, it activates a (non latching) relay...

The base is grounded through a simple external footswitch.

The problem is that, when the pcb is installed in the enclosure, the Jacks touch the enclosure (grounding it) and this makes the transistor to not work any more...
But when the Jacks don't touch the enclosure it works perfectly...

Why??

Can you help me?

[mjg]

Can you show us a schematic of what you are using?  That might help understand. 

Photos of your foot switch and circuit?

I'd make sure that your foot switch soldering isn't shorting to the body of the switch.  If the switch body is connected to the switch lug somehow, and the enclosure gets grounded (as it should), then you will end up with an always grounded switch. 

[helos]

Here's the schemtic...
VC= 5V
VA= 0V (which is connected with a little wire to the DC ground)

I've just found out that the transistor should be 180° rotated... but still doesn't work... The fact is that, when the jack is not plugged in, if I connect the sleeve and the tip of the jack, the transistor perfectly work. But when I plug the jack this makes VA touching the enclosure, and the transistor doesn't work anymore...

[mjg]

Ahhh, right, I didn't understand that the foot switch is remote, and connected via the jack. 

I think it should work... Double check that you have not swapped the tip and sleeve  connection of the jack?  It should not matter that the sleeve is grounded on the enclosure, as wont that only connect to the tip when you press the foot switch?

[helos]

I've checked all the connections and are all good... Actually the jack is the "amp jack" and it's soldered directly on the pcb, so there's no wires that I could have wrongly connected...

I just wanted to recreate the JHS "red remote" channel switch circuit... But I can't find out why it perfectly works until VA is touching the enclosure...

Paradoxically, if I test the pcb outside the enclosure, with all Jacks plugged (In, OUT and the fottswitch) it works perfectly...
But when I install the pcb inside the enclosures and even one jack touches the enclosure... It just stops working...

[mjg]

I'd check that there isn't any other part of the PCB accidentally shorting out when you put it into the enclosure. 

As a next step, maybe try touching each jack to the enclosure with some spare wire or something, to see if you can narrow down if it's a particular jack causing the issue?

Try a multimeter to measure the voltage of the tip and sleeve of the jack when it is out of enclosure, and inside enclosure, to confirm that it is behaving differently. 

Maybe some pictures might help someone work out the issue. 

Good luck.