Potentiometer with switch and LED

Search for 'clear shaft potentiometers':

Theo

I had such a thing in a car once. Push pull and turn to dim Had a lamp in it. Sadly I cannot remember what car it was. Maybe an Opel

You can also get 'shaftless' pots:

Use one of those, put an SMD LED underneath and then your own transparent shaft/knob arrangement?

Theo

How large do these indicators need to be? You could get away with a very small hole in the panel with a high intensity surface mount LED hot glued or epoxy glued behind it.

I assume that you are using a knob on the shaft. Drill a hole in the front panel inside the diameter of the knob (towards the outside diameter of the knob) and again glue a surface mount high intensity LED behind the hole. The pot could be stood off by a few mm with a few washers or extra fixing nut to make room for the led. The light will glow behind the knob. Perhaps use a semi transparent knob.

An alternative is to use a light pipe or butcher something like a plastic optical cable used for digital audio (TOS link). The led then could be positioned elsewhere with more room.

Is it practical to use rotary encoders? If so, they exist with transparent shafts and various coloured LEDs and momentary action switches. There are suitable translucent knobs.

Sorry, wrong type of pipe for your application. You want one where the majority of the light comes out of the end.

Ahah, that's a term that I've not tried.

That could work - I'm after panel mount rather than PCB mount, but I could get around that.

It used to be common on car radio knobs, but not so much these days.

That wouldn't look right. It either needs to be within the control knob or a 12mm warning lamp, matching the others.

That sounds like a possibility. I was just hoping to avoid extra work and separate components, when a suitable device might exist (they certainly used to on some car radios).

There'd be no need for that, as there is sufficient space behind the panel.

Possible. However, I would have to use a digital controller to read the encoders and drive the inputs to the PWM motor drivers. Whereas pots can directly interface to the drivers.

These look nice

Yes, I did find those later on. It looks like they are set up to supply in bulk to industry and I've not found a retailer selling to the public yet.

Once people had used various terms, I had something useful to search on and turned up more. Some of which would look more in keeping (more old fashioned) with the rest.