IBM 029 card punch

[Christian Corti]

Hi,

I have here three IBM 029 card punches, two model A and one model C (with 
interpreter) including documentation. So far so good. I do have an 
additional 029 (I *think*) without covers which I would like to restore. 
The problem is that it is "a bit" different from the other three punches 
and I would like to know what model this is and if anyone has the 
maintenance manual for it.
The mechanical part is almost the same as in the A and C models, but the 
keyboard has two lights, one at each side. I know that the light on the 
left side is an indicator for the verifier, but the one on the right side 
is unknown to me. It is a printing punch and has two program drums each 
with 12 star wheel contacts (instead of the usual 8 on the front drum).
Now comes the electrical part: It is very different from the other three 
punches. It has more SMS cards (about 12, not including the cable cards) 
and many more wire relays (no reed relays and no electronic components 
except for some diodes, resistors and capacitors). But the most 
interesting feature of this unit is the "I/O" port on the rear left side. 
Does this ring a bell to anyone?

Thanks,
Christian