Footswitch grounding

All frequent questions on switching: true or not true bypass, transistor-based or mechanical.
Post Reply
User avatar
McHuge
Breadboard Brother
Information
Posts: 58
Joined: 12 Dec 2012, 11:18
Has thanked: 8 times

Post by McHuge »

Does the casing of the footswitch have to be ground? I have finished a treble booster for my board and that is housed in an aliminum box but the pot, switch and 3pdt footswitch are housed on a non conductive surface. Before I Installed it, the booster worked like a charm but now I have installed it, every metalic part of the board makes a sound when I touch it and there is now a ground loop buzz. I've used the audio beavis instructions on wiring a stompbox and I have double checked it. The effect works but the buzzing is doing my nut it!! I just wondered if I grounded the casing of the footswitch it may solve the problem.
Hope this makes sense!! :oops:

User avatar
Dirk_Hendrik
Old Solderhand
Information
Posts: 4193
Joined: 03 Jul 2007, 08:44
Location: Old Amsterdam
Has thanked: 232 times
Been thanked: 887 times
Contact:

Post by Dirk_Hendrik »

Seems there's no circuit ground connection to the case.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

User avatar
McHuge
Breadboard Brother
Information
Posts: 58
Joined: 12 Dec 2012, 11:18
Has thanked: 8 times

Post by McHuge »

You mean from the switch to the aluminium case?

User avatar
Nocentelli
Tube Twister
Information
Posts: 2222
Joined: 09 Apr 2009, 07:06
Location: Leeds, UK
Has thanked: 1152 times
Been thanked: 954 times

Post by Nocentelli »

Dirk is wondering if your metal case is actually grounded: Buzzing when you touch it suggests it is not. The metal case would normally be grounded by the sleeves of the input+output sockets IF you're using metal (uninsulated) jack sockets. If you're using plastic insulated sockets (i.e. where the cable sleeve lug is not electrically connected to the part of the socket that touches the case) you'll need to make a separate ground connection to the case to provide shielding. You should not need to ground the stompswitch - If the case is grounded, the metal parts of the FS that touch it will also be grounded. While you're at it, check that ALL points that should be connected to ground, i.e. power negative, circuit ground, input/output sleeves, volume pot lug 1 etc, are actually connected to the same common ground.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

User avatar
McHuge
Breadboard Brother
Information
Posts: 58
Joined: 12 Dec 2012, 11:18
Has thanked: 8 times

Post by McHuge »

All grounds are connected to the ground on the output lug of the socket. The case itself is a AC mains socket chassis (I'm skint and I heard they do the job!!) so it is conductive plus it has an ground point which again is connected to the out put lug. The footswitch then goes of to an another mains chassis box but with a hard wood lid that houses footswitches for the booster, amp channel selection and the reverb (following this?? :D ). One of the lugs on the footswitch goes to ground so I figured it would be earthed.
Another theory I have discovered is it could be my power supply. Its a cheap ebay daisy chain job. Would a proper iscolated power supply be the solution??

Again, I hope you get this :oops:

Post Reply