b. Common-battery telephones.
(1) TA-838/TT is a rugged, solid-state field telephone It is used with the SB-3614 switchboard.
It can also be used with the AN/TTC-38, AN/TTC-39, and AN/TTC-S9A. When using the TA-838/TT
in the 4-wire mode, it can have up to three extensions on one phone. When we use the TA-838/TT in
the 2-wire mode, we can only have one extension from one telephone. (See Appendix A, Figure A-4.)
(2) TA-938/G is a 2-wire common-battery telephone set intended for use in a sheltered area.
You can bridge two sets across a single 2-wire line for extension service. (See Appendix A, Figure A-
(3) TA-954/TT is a 4-wire terminal. The TA-954/TT can send and receive conditioned diphase-
modulated digitized voice. It can send and receive information at 16 or 32 kb/s rate. The TA-954/TT
provides digital communications interface with the joint communications (TRI-TAC) and mobile
subscriber equipment (MSE) switchboards (See Appendix A, Figure A-6.)
(4) TSEC/KY-68 digital subscriber voice terminal (DSVT) provides encryption/decryption voice
traffic service. It can also provide secure digitized data traffic service. The TSEC/KY-68 operates as a
full-duplex or half-duplex terminal. The TSEC/KY-68 provides secure and nonsecure access to
switched networks. (See Appendix A, Figure A-7.)
(5) TA-1035/U digital nonsecure voice terminal (DNVT) provides full-duplex, conditioned
diphase-modulated digital voice service. It can also provide loop signaling information with wire and
mobile access equipment. The TA-1035/U provides a data port for interfacing the SST and AN/UXC-
7A devices. (See Appendix A, Figure A-8.)
Types of switchboards.
a. Tactical switchboards are divided into two major groups-manual battery and common-battery
equipment. At brigade level and up, we find common-battery equipment housed in mobile units.
b. The mobile units get prewired and designed to accommodate the equipment needed for the
mission. The shelter has cable receptacles for connecting the 26-pair field cables. They usually contain
electrical heaters to warm the personnel and equipment during cold weather. A trailer-mounted power-
generating unit provides electrical power to the shelter. The next few subparagraphs examines the
different switchboards found in the field.
(1) SB-993/PT is 6-line analog 2-wire manual switchboard, capable of supporting a maximum of
six local-battery telephone circuits or six trunk circuits. (See Appendix A, Figure A-9.)