Mutron Biphase Clone: Help selecting a rotary switch:

[Strategy]

I've been building a Papareil (Marc Bareille) Mu-Tron Biphase clone from his pcb's. Relatively early version of the project. The rotary switch is not listed in the parts list and Marc says to me on email, "pick a Lorlin or Eagle 3 position switch".

Admittedly rotary switches are often completely confusing to me and I've been searching mouser and small bear for both Eagle and Lorlin brand switches without really completely understanding what I'm looking for. Here's how he draws it in the wiring diagram, and I can post a detail of that portion of the schem if it's helpful. I don't have PDF of the docs, I think I got a paper packet with the PCB's at the time. Been whittling away at this one for years!

I'm grateful to this community's sage wisdom of all things rotary!
Strategy

[antonis]

Can't perceive from your photo, but...

A 3 position rotary switch is a switch with a central lug and 3 "secondary" lugs..

The central lug is connected to only one of secondaries accordingly to switch lever possition..
(you have an incoming signal which can outcome from 3 different exits but from only one at the time..)

There are of course more complicated rotary switches like dual pole 3 positions or x pole / y positions in general, where x stands for number of central lugs and y stands for number of secondary lugs..

If you need a single pole 3 position rotary switch you may obtain the same result with a SPDT switch (ON-OFF-ON) but it depends on your specific circuit need..

[duck_arse]

lorlin come in 1p12t, 2p6t, 3p4t and 4p3t. I think. they used to, anyway. any one of these varieties will suit if your circuit is a single pole, three position switch-needer. there is a washer-with-pip under the mounting nut that you can rotate to set the number of positions clickable, with any extra positions - well, extra.

[antonis]

Preferably the last one (4P3T) for not switching through 9 dummy positions.. 

[Strategy]

Thanks all! I can see that there will be a lot of unused lugs which is no problem
Just got into a quagmire of freedom of choice of number of poles/throws, but then also weirdly about Mouser many of the varieties are non-stocked. I will keep checking other options I believe that Small Bear stocks the 4p3t or similar -- similar to the switch specced in lots of projects like Lovetone clones, even some Madbeans projects etc. (IIRC?)

[Processaurus]

Use the SP2-12T, like here:

http://smallbear-electronics.mybigcommerce.com/26mm-enclosed-1p2-12t/

It has 12 positions available, but there is a special tabbed washer that fits into the switch, that stops it from clicking to the unused positions. You decide how many positions it has. You just put the tab into the right slot, for the number of throws you want.

[Strategy]

So last Friday at my local electronics supplier I found a 2p4t -- seems like it will work although one of the poles will be unused.
Will report back on my progress...looking forward to finishing this beast! (and what I am guessing will be a slog through some trouble shooting)

Strategy