I am actually wondering if it is a differential encoder just without the wires connected. If you had a scope it could easily be tested but sadly you dont

Hood

Going by the 3 additional tinned holes on the PCB, I'd guess it is differential without the wires.

You could check with a multimeter to see if they change voltage when turned to a few random positions, or if your meter has a frequency setting, while spinning it.
The Z would be easy to figure out, but the other two could be a bit more problematic. The trick would be holding the encoder at a point where A and B are in different states (i.e. one high, one low), then matching to their complimentary outputs.

I'll check the tinned holes later, I noticed yesterday that one of them had no tracks going to it top or bottom, maybe I should just order another encoder? Was thinking about the amt103?

If that is the capacitive ones, I have heard they are reasonable, however I have never tried any of them. I think they will be single ended so you will need a line driver for it as well.
Hood

I've ordered some AMT103's now and line drives. although I'm mr impatient and I really want to get my machine working tonight. If I connect the old encoders incorrectly, could I damage my controller, (assuming I get 0v and 5v correct)

No, I dont see how you could.
Hood

I took the safer option, and waited for my new encoders and line drivers to arrive. I purchased an extra one or the spindle too. Hopefully order the threading module when I get some spare cash.

I've been spending all my time reading the wiring diagram and tracing cables in my bridgeport. I do have limit and home switches. Currently all my limit switches are joined in series. Is there any advantage to connect each limit switch to it's own input on the IP-A?

I just have mine in series however I think if you have separate the the CSMIO will not allow you to jog the wrong way after you reset, could be wrong on that however
Home switches need to be separate for best results though.
Hood

ok thanks for the advice hood.

I managed to mount the new AMT encoders last night. I modified the old end cap to put a large flat area to mount it on. I didn't realise how tiny these encoders where