[sdiy] rotary encoder?

[Matthew Smith]

Quoth mark verbos at 2009-01-08 11:32...
> I have a situation where I'd like a 12 position rotary switch to  
> output a parallel 4 bit digital word. I searched absolute rotary  
> encoder at mouser and they're $88. Isn't there a cheap part out there  
> that does that? Obviously, I could use 50 diodes to make a regular  
> rotary switch do that...

How about a cheap encoder that does 2-bit Gray code?  You could use it 
with a cheap microcontroller to put out your 4-bit code.  (Probably 
cheaper to use an MCU than discrete logic.)

I've seen several listed in China on eBay like this:

<http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=400020432401>

I've got some similar for a MIDI control surface I'm designing.  I'm 
using pots and ADCs for single-byte controllers and encoders for 
dual-byte controllers.

Cheers

M

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Matthew Smith
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