hi, im trying to figure out encoder pinnout. i made some conclussions. im i right?
Wire it up and try it. Put a voltmeter for A or B to ground and you should see a square wave (turn the encoder very slowly). If that doesn't work then put the voltmeter from A or B to +v. If that doesn't work, swap +v and ground, and repeat.
Hi,
I would agree with @SteveMann.
However output A and output B may need each to have a 1K resistor form A to Vcc and B to Vcc.
The output is probably open collector photo transistor.
Tom.... 
i wired it up, i can read 2V between gnd and a, same with b, is it ok? i used 4.2k pull up for each output
Francisco-Colli:
i wired it up, i can read 2V between gnd and a, same with b, is it ok? i used 4.2k pull up for each output
Sounds good for those resistors, what happens when you put an opaque object in the gap of the sensor?
That, is block the LED IR/light getting to the optotransistor?
Thanks.. Tom..