Wtill this cause noise or other issues?

[daz]

Stupid question because i see no reason it won't work but then again i'm not particularly smart with electronics theory so thought i better ask b4 doing the work. Putting a few pedals on a board and want to run them with batteries. But pulling cables to stop drainage when not in use won't be an option. So i was going to put a switch on the board to cut the ground connection for the batteries. I measured resistance between each of the 3 pedal from their battery clip's ground snap to the pedals ground and all shows a dead short, and from that i determined the pedals are all the same as far as grounding schemes and it should be fine. But there are issues i may not be aware of like ground loops and such. So all 3 pedal's battery grounds would be tied together at a switch and the other side of the switch would go to a ground on one of the patch cables. Any potential issues?

Also, what about 2 of the pedals sharing a single battery? Dumb idea?

[J M Fahey]

In general internal batteries are grounded at each pedal through the "unused" contact in a Stereo jack, and that at each one, youŽd need one switch per pedal to do it right.

I would build *one* large capacity battery pack using Lithium or NiCad batteries with enough capacity to feed all pedals for many hours, this will give you "mains independence" which I guess is your goal, and can be switched OFF with just one switch.
In that case you can switch the "+" line which is conceptually easier, of course you can also switch the negative terminal if you wish.

IF battery choice gives you multiples of 3.7V so no exact 9V available, you can go "one step higher", say 11.1V nominal, and use a low dropoff regulator for *perfect* 9V

[daz]

I just need one switch IF as i asked theres no problem combining the ground wires from each pedal's battery ground. What i would do is connect eack pedal's battery ONLY to the + of the clip. The - of each clip would be taken out from all pedals and combined and go to a switch. The other side of the switch would go to the ground of one of the signal patch cables. Not sure why i would need a switch for each unless u r suggesting it is NOT ok for all 3 pedals to have thier battery - wires combined together. Is that what u r saying? I figured that wouldn't matter since they are all dead shorts to ground. The input switching jacks should have nothing to do with since they are always plugged in so i'm not sure why u mentioned that. I'm probably missing something here. By the way it's a tiny board with no room for a battery pack.

Ahhh, just realized i didn't explain fully....the 9 volt batteries will be mounted in clips outside of the pedals.

[daz]

well, noting like doing it to realize why it won't work. DOH ! But no way i'm gonna use 2 switches, i'll just use a tripe or quadruple pole switch. i know i have 1 around here somewhere.

[pdf64]

Each pedal could have its battery disconnected by inserting a dummy plug into its external power jack.
So they could still be left with the signal input plug in place.

[daz]

Yeah, but that would be a PITA considering at home i sometimes plug in many times during the day often for just a minute or 3. Doesn't matter because i had a mini switch thats two DPDT's in one and that worked perfect.