Help identifying a part needed (optical rotary encoder elements)

Thread Starter

Raph8585

Joined Sep 12, 2020
3
Hello all,

I was wondering if you could help me identify a part (actually 2 parts) from a rotary encoder. It's a nice, heavy duty dual concentric switch from an old piece of avionics. I'm trying to find out more about its optical components . It has 2 emitters and 2 detectors on each deck, with a nice glass domes. I have no idea if they work in a visible light spectrum or IR, or how to drive them. What's kind of odd about them is - they don't have leads - the whole package goes through a hole in the PCB and the bottom part is soldered on the other side. They are tiny - about 2mm (0.08in) across.

Has anyone seen anything like this before? Or at least any ideas how to (non-destructively) find out its operating voltage?
 

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dreamsofhabit

Joined Sep 11, 2020
16
What is the avionic component? I might have more luck finding info if I knew where it came from.
Also, I happen to work in the industry. I can ask some avi guys when I go back to work and see if they recognize it, or can give me some direction
 

dreamsofhabit

Joined Sep 11, 2020
16
Well, good news and bad news. I'll start with bad.
I can't find much on the parts from Gable, to access further information you have to have a login which you can get by buying products from them (side note, it may be worth contacting support with them and asking). Aviation parts are relatively difficult to research without the proper login/access.

For the good- Gable does list a pricebook on the site found here: https://www.gableseng.com/pricebook/
the part closest/most likely culprit is 700-D32336A SWITCH SHUTTER MINI - DUAL
here's one I found online : https://www.taobao.com/list/item-amp/607659360027.htm (you'll probably have to convert the webpage to english)
I suspect it operates very similar to a RES20-100-200-Z.
https://www.digikey.jp/product-detail/ja/nidec-copal-electronics/RES20-100-200-Z/563-2071-ND/6469507

But, I'm no expert with encoders. So, tread lightly. Hopefully, this can be of some use to you.

Edit: I am wondering if those glass domes/emitters are strictly for illumination of the dial?? IDK. food for thought.
 

Thread Starter

Raph8585

Joined Sep 12, 2020
3
Thank you so much for your effort! Yeah I figured there's no way of getting that info from the manufacturer of the panel (GABLES), as they buy them (switches) from someone else and the manufacturer of the switch gets the parts from yet another party as well. I was wondering if maybe someone has seen or have some info about the optical elements.

I know the operating principles of that switch, those domed elements are emitter and detector (domes are required to produce a narrow beam on the emitter and to convert it back to a wide beam on the detector side). There's a slotted disc in between them fixed to the shaft, so when you turn the shaft one pair will be obstructed and the other will have a clear view - and will produce a square wave pattern you can use to decode the direction of the turn. The whole system is optical, there a no contacts to worry about.

I'm trying to figure out the safe voltage to drive the emitters, and what to expect on the detector side. I figured I'll ask before I go for a trial and error route with my bench power supply and a scope. I really don't want to damage them as they are expensive and hard to obtain.
 

MaxHeadRoom

Joined Jul 18, 2013
21,426
It seems as though the shutter for each is just a complement of the other, not the usual 90° quadrature type, which is used to detect both position and direction of rotation.
Max.
 
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