Need help identifying a part

Hi all, I've got hold of an old remote control and I'm trying to identify a part. Its a mitsubishi RM M54-42402, you can see a picture here: (2nd picture), the part I am interested in is the jog wheel. All its got on the part is alps 120H JAPAN, its got 2 groups of pins on it, a set of 3 and a set of 5.

on the circuit board the pins are marked left to right, 1,2,3,C1,4 and J2,C2,C1.

Hooking up a dmm I have determined that the set of 5 pins are for the outside part of the jog wheel and seem to provide 2 switches? for each side of centre that you move it, depending on how far left or right you move it will give a reading on one of the pair of pins with the other probe connected to C1 (which I think is common?).

the set of 3 pins I don't really understand, using the same technique (- probe on C2) I am reading resistance when I wind the jog wheel round but It doesn't make sense to me, I think its a quadrature encoder but I don't have a clue how to hook it up to the arduino, both issues here being down to my lack of understanding/experience of electronics I guess. Do I need some kind of resistor in line for each of the inputs?

Can anyone help me with understanding this part or point me to some info where I can try and find out about how to use it? Google wasn't very freindly I'm afraid.....

It's a really robust solid feeling part and is ideal for some projects I have in mind, best of all it cost me £1 :)

Does this help? It's not the same part, but it's probably similar. "C" is probably "common" and the 1-4 output a "gray scale" code (different pins connected to the common) depending on the absolute position of the dial. I haven't got much of a guess for "J" - does the wheel have a push-button operation as well?

ALPS is a major manufacturer of switches and similar electro-mechanical parts, but they're not very friendly to the hobbyist market; finding data on their parts is difficult, and they seem to obsolete things at a furious rate (perhaps most of their stuff is semi-custom?)

hi Westfw, The unit consists of a central 'dial' that I call the jog wheel it is connected to the set of 3 pins, and outside of that is a 'collar' that you can grab and twist left or right, it is spring loaded and connected to the set of 5 pins.

Thanks a million Westfw, That looks uncannily exactly like the part, the jog part has 10 positions, would that equate to the jog output code of 10 pulses on that data sheet? Now I've read a little more on encoders I wasn't ever going to discover what was going on on the encoder part measuring resistance on one pin + common :D Good to see I got the 'shuttle' switches right though :)

Another "better late than never" reply here...

I've got some notes on this Learning About VCR Jog Wheel page which includes a link to Jogging and shuttling with Arduino which is the best reference I've found.