background: putting a rPi in my vintage car, and wanting appropriate looking switches for my vintage. I have the matching key cap / knob caps for my dashboard, but now need to source the right components to mate to those keycaps and connect back to pi, but what switches am I describing?and for 10,000 Points, include link to said component.

So: I need 2 kinds of switches and I'm having a hell of a time here bewildered on digikey and mouser lost in a forrest so hoping reddit comes to the rescue.

Can someone help a) name them and/or b) point me to a link / part number / source? Both should be panel mountable if possible. Both should be slotted shaft if possible (if not, I can cut a slot into them by hand) and both should be 4.5mm shaft diameter if possible.

1 of them should be ROTARY with 3 positions: hi / off / low (for a seat heater pad in a car... sold on amazon by the thousands, but with ugly rocker switches. not appropriate for a vintage car.. but rotary switches with the right knobs from that vintage is why I want to do this). what is the 3 position 12v/2amp hi/off/low switch I need here? what's it called and/or do I have a prayer of finding it with a smooth or slotted 4.5mm shaft (at least 15mm long) panel mount?

The other of the 2 types needs to have 2 states. and therefore could be a push button OR a 2 position rotary switch, but here's what it needs to do: in state 1 it needs to cut power to circuit A and send 12v of power to circuit B (powering up an antenna), and in state 2, it needs to cut power to circuit B and send 12V of power to circuit A (powering up a bluetooth receiver unit). So what is this kind of switch called and how would I wire it? and for a free beer any time you are in portland! send links to both/either with a slotted (preferable) 4.5mm shaft or smooth shaft that is at least 10 - 15mm long (can cut down if longer) and panel mounted.

too much to ask or super common? If you have the above, I'll buy them from you! okay thank you.


  • Your question is a bit confusing. For instance: When you ask for a rotary switch that does exactly what the toggle switch does, that would theoretically prevent you from needing an RPi. If you want to control the wires from the toggle switch with the RPi, then the switch you need is going to be different than the toggle switch. When you ask for a switch that sends 12V power to two different circuits, then, once again, that would theoretically prevent you from needing an RPi. This is an easy one if you're not using an RPi, though, it's a single-pole double-throw switch. Why RPi? – rpseu Jul 10 '19 at 14:21
  • The first switch you are looking for is a 3 position rotary switch, the other two are 2 position - 2 pole rotary switches. This is overkill because it has 4 poles, but should look like what you are seeking, mouser.com/ProductDetail/Grayhill/… – Glen Yates Jul 10 '19 at 14:23
  • Are you able to post a picture of these switches? – Marcel Jul 10 '19 at 19:40

Here's a quick attempt to help you find the first switch: https://octopart.com/search?q=rotary%20switch&start=0&specs2.483.numbers=3&specs2.41.numbers=(16__600)

I started at octopart.com (which I recommend at least looking at; they have pretty appropriate filtering aids and entered the string (in quotes), "rotary switch".

I then entered 3 for the number of (switch) positions

And 16 -- 600 VDC for the overall DC voltage rating.

I didn't do the mechanical form-factor match or the current rating; I leave that to you.

Hope this helps

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