ciaraldi@cs.rochester.edu (Mike Ciaraldi) (06/02/88)
I'm helping someone who has a PDP-11/73 running TSX and an LA180 printer connected to the standard DEC parallel port (the board is called an LPV, I think). For those who came in late, this is not a Centronics interface. He currently has a 25 foot cable from the computer to the printer, with a 40-pin socket connector on each end to mate with the headers on the parallel board and the printer. The cable itself is round shielded cable, with about 40 conductors. DEC calls this a BC11S cable, aqnd used to sell them through DECDirect in 25-, 50-, and 100-foot lengths. The 100-footer was almost $400 in 1980, according to an old catalog. He wants to move the printer farther away (50 feet), but is having trouble finding a new cable. So, he is thinking of making one himself, either a 50-foot new cable, or a 25-foot extension. So, the questions are: 1) What is the maximum length for proper operation of a DEC parallel printer cable? 2) Can we just make one out of 40-conductor ribbon cable by crimping mass-termination socket connectors on each end? Will this give the proper pinout? (It should on an extension, at least, but the manual is unclear on the cable). 3) Would 50 feet of ribbon cable carry this signal all right? The pinout seems to use alternating signal and ground wires. Would using shielded ribbon cable help? 4) Is there a good, inexpensive source for cables like this? We called a couple of computer-supply places without success. Thanks. Mike Ciaraldi University of Rochester Computer Science ...rochester!ciaraldi or ciaraldi@cs.rochester.edu