This is what you need to do to extend the HandPunch RS232 cable
 
This is what you need to do to extend the HandPunch RS232 cable:

It comes with 50 feet, and a green connector which goes in to the handpunch clock. You want to extend it.  We can do this up to 150 feet, using the right materials.  Materials needed:  Shielded CAT5 cable and wire nuts - or better.

CAT5 cable 101:
In a CAT5 computer cable are several sets of wires.  They are in pairs, and each pair is twisted together.  The twist cancels computer noise, which works fine for standard CAT5 use, but not for the RS232 hand punch.   You must use one wire from a twisted pair, not both wires from the same twisted pair.  That's the trick.  And it must be the shielded cable, not unshielded.  If you use unshielded, it will not work.  Shielded cable has a tin foil wrap that goes in between the pairs and the rubber tube that the cable is in.

Cut 3 to 5 feet off of the RS232 end of the original 50 RS232 cable.  Connect one CAT5 wire to each of the three RS232 wires.  Note which wire from the original cable is connected to which color wire of the CAT5 cable.   At the hand punch, cut the original handpunch cable about 1 to 3 feet back from the green handpunch connector.  Connect the correct CAT5 wire to each of them. 

Go back to your software and test the connection, it should be fine.