[ofb]

i figure i'm missing a basic truth and hope someone will enlighten me. i want to make a simple switchbox that requires a single throw and six poles. i figured such a switch would likely be rotary for hardware simplicity, but since digikey only carries up to 4p, i now suspect i'm just asking the question wrong.

there's no such thing as a st6p? what does one do then?

 

[tangent]

Perhaps we can come up with an alternate configuration if you tell us what it is you're trying to accomplish. You may not truly need SP6T.

 

[ofb]

fair enough, though i have to admit it's not headphone related this time. apologies.

friend would like to switch between his ps2 and vcr without changing cables. so, two sets of 3 rca in, one set of 3 rca out.

which i figured would be simple, plus a little fun making a case & knob to go with his funky decor.

 

[tangent]

I'm glad I asked. If you use composite video, you only need a 3PDT switch: 3 poles for the outgoing wires, two throws for the incoming sources. You can get these in toggle or rotary switch form. The rotarys will likely be 4PxT (i.e. configurable number of throws, up to 3), but you can set it up how you like.

You'd need more poles if you used S-video or component.

EDIT: Obviously this assumes you can do a shared ground setup. If you must also switch the ground connections, you'll need a 4P switch.

 

[ofb]

great. thanks for this.

i'd thought i could use shared ground, but to cover bets had a look for 6p switches too. when i couldn't find those i figured i'd better go back to 101's and enquire why they're not around.

now i'll presume there's just little call for such a beast.

thanks again.

 

[tangent]

Hang on there. Just because you have to switch the ground doesn't mean you have to use 6 poles. All three grounds for each component can definitely share their grounds. The question is, can the Playstation and the VCR share grounds? They should be able to, so you should try it and see. But if it doesn't work and you're sure of your soldering job, that's what I'd blame first. If you need to switch the ground, you only need 4 poles.

 

[ofb]

aha! i just knew i was skipping a basic that was going to be embarassing. of course the grounds can be grouped... d'oh.

sorry, man. my head is still in a work project.

i don't know if the ps2 and vcr can share ground happily. since they're not mine i think i'll just be cautious and grab a 4p. thanks.

 

[tangent]

You're not likely to damage anything if there's a problem combining both device's grounds. It'll just look ugly. You can easily test it beforehand: run a jumper from the VCR to the PS, touching the RCA grounds on each, while watching the PS and the VCR separately. If touching the wire from one RCA ground to the other doesn't cause problems, it'll work when you lash up your switch box, too.