IBM 5280 User's Setup Procedures page 145

b. Put the wrap connector in the protective recess area of the machine
verification binder.
c. Push the EIA or DDSA connector into the socket on the modem
or channel service unit and turn the thumbscrews until tight.
From 5288 or 5285
""
Modem or Channel
Service Unit
(It is probably located
on a table near the
display station.)
d. Push the connector into the telephone line socket.
or Service Channel
Unit Connector
Telephone Line Socket
~ (It is probably located
~
.; on or near a wall.)
,,' - 0
<)
, I)
/
,"
"
,
Push In
User's Setup Procedures 139