IBM 4247 - Model 001 B/W Dot-matrix Printer, User Manual

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Telephone Twisted-Pair
The printer can also attach to the host system or controller by a 110-ohm
Telephone Twisted-Pair (TTP) cable.
The printer requires a special signal cable for attaching to the TTP wiring method.
The cable must have a balun, a length of coaxial cable with a bayonet connector
(BNC) on one end, and a length of telephone twisted-pair cable terminated in a
miniature 6-pin modular plug at the other end (CTPA). The balun is used for
converting from coaxial to telephone twisted-pair wiring. The IBM part numbers are
provided in the chart below. If this method is used for attachment, the maximum
cable length between the printer and host system or controller is 270 m (900 ft). A
balun is required at the host system or controller end.
Baluns are also available from other manufacturers. Some of them do not include
the wire necessary to attach the printer to the wall-mounted modular telephone
jack. When these baluns are used, it is important that the proper wire be selected
for making this connection. Note that even short lengths of common parallel
telephone wire, such as that sold by telephone and electronic retail stores, may
cause malfunctions in your printer. To obtain proper wire for this use, see your IBM
representative.
For detailed information about the Telephone Twisted-Pair cable, see the
IBM/ROLM Planning and Installation Guide for the 3270 Coax-to-Twisted-Pair
Adapter, GA27-3722.
IBM Part No. Description
IBM 61X4584 5.9 m (18 ft) - Coaxial to TTP Adapter (CTCA)
Appendix A. Printer Specifications
A-15