AT&T System 25 - Manual (Page 136)

INSTALLATION
INSTALL CUSTOMER’S DTU
The DTU must be directly connected to Port #3 on the CPU/Memory CP
(Figures 2-45 and 2-46).
Remote and switched connections are not
supported. Follow the procedures provided for installing the SAT.
INSTALL STATION MESSAGE DIGITAL
RECORDING (SMDR) EQUIPMENT
The SMDR equipment connects to Port #2 on the CPU/Memory CP. The
connections are the same as those for the SAT (Figures 2-45 through 2-48).
Follow the procedures provided for installing the SAT.
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