d. Preprogrammed conference. Pick up the handset and listen for the dial tone. If priority
calling is wanted, press the R key and a priority digit. Press the digit keys for the number assigned to
the conference. Press and release the C key. Wait for everyone to answer. Release any unanswered or
busy number by pressing the R key for one second and releasing.
23. Special operations when used with AN/TTC-38 switching facility. The AN/TTC-38 switching
facility has the capability for special trunk services and information calls. Procedures to access the
special trunks are provided. To place an informal call, you merely call the specified number.
a. Pick up the handset and listen for the dial tone. If priority calling is wanted, press the R key
and a priority digit. Press and release the R key. Press and release a numbered key corresponding to the
Key 5................... SF commercial trunk
Key 6................... Wideband trunk
Key 9................... Defense Switched Network (DSN)
b. Press keys for the desired number.
24. Extension service is available with this telephone. The first and succeeding telephones, up to a
maximum of four, are connected to the man line in the same manner as the original. (See Figure 1-7.)
Figure 1-7. Cabling for extension operation.
PART C - TELEPHONE SET TA-838( )/TT
25. This is a 4-wire tactical telephone capable of 2-wire operation that can be used in mobile
subscriber equipment (MSE) units and units equipped with digital group multiplexer (DGM) equipment.
It is a ruggedized, solid-state field telephone. It can be used as a desk telephone or installed vertically.