IBM 3274 51C Maintenance Information page 172

Jumper for 56K bps (Note 1) _ _ _ _ _ -,.
Always Jumper - - - - - - - -.....
(Note 2)
Jumper for 9.6K bps (Note 1)
Jumper for 4.8K bpS (Note 1)
Jumper for 2.4K bps
(Note 1)
Notes:
v
1. Install jumper (2731801) to select 56K bps, 9.6K bps, 4.8K bps, or
2.4K bps. Speed selected MUST match the speed of service
supplied by common carrier.
2. This jumper MUST always be instal/ed.
Figure C-12. DDS Adapter Card Jumpering (Card No. 14),
U.S. and Canada Only
Appendix C. Connector, Board, and Card Locations C-9