[sdiy] Shaft Encoders (was "illuminated switches")

[Matthew Smith]

Quoth Eric Brombaugh at 2009-04-25 08:21...
> * The quadrature signals don't go through a full cycle for each detent - 
> Boo! Rather, the detents are every 90deg in the quadrature sequence. 
> This behavior makes these encoders incompatible with the more common 
> Alps variety where the detents are spaced every 360deg in the quadrature 
> sequence. Firmware and/or hardware decoders designed for Alps won't work 
> correctly with these encoders - you'll have to cycle through 4 detents 
> on these encoders to register 1 pulse on a decoder designed for Alps.

I have some of these from a Chinese eBay vendor, have yet to deploy.

Now here's a possible tip, noting that in doing this you'd lose the
push-button functionality:

If you want to use a really cheap encoder but require more codes per
rotation, think back to the (variable capacitor) tuning mechanism of old
radios: use gears. This could include actual plastic gears (also quite
cheap) or a belt or cord drive.

Just an idea.

Cheers

M

-- 
Matthew Smith
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