On Wed, 13 Aug 2008 07:42:14 +1000, Franc Zabkar
put finger to keyboard and composed:

On Tue, 12 Aug 2008 11:47:29 -0700, "Hoi Wong"
put finger to keyboard and composed:

The part# on the service manual is no where to be found, neither does it
contain much information:
http://www.stanford.edu/~wonghoi/DC/4600-05-0211.png

I just probed the connections to the Wavetek 75 board, and it seems like one
wire is grounded while two are hooked up to +5V (My mechanical encoder was
too broken to tell which lead is which). Is there any opto-encoder that
you'll recommend for this case?

Thanks.

Cheers,
Hoi

Page 121 of the Model 23 manual shows that pin 3 of SW1 is grounded
and pins 1 and 2 are switched to ground. The switched pins connect to
IN1-0 and IN1-2 of the uProc/Synthesizer PCB (page 126) via pins 1 and
2 of J13/J12. These inputs are pulled up to +5V via R21 and R22.

How about this 2-bit, 64 pulses/rev rotary encoder:
http://www.digikey.com/scripts/DkSea...D-E28-L064N-ND

Datasheet:
http://www.bourns.com/pdfs/em14.pdf

Digikey have 2 other suitable encoders in that same series that I can
see.

The above encoders are optical types, so you will need to wire up a 5V
DC supply.

- Franc Zabkar
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