Commanders and staff require fast communications on a personal level as often as it is available. In
garrison, there is no problem since everyone has a telephone on his desk. However, when the unit goes
to a tactical situation in the field, they desire the same fast communications that were available in
That is where the wire systems installer comes in. It is his duty to install tactical telephones from a
priority list that permits the commander and his staff to have the same type communications as was
available in garrison.
There is a need for point-to-point communications for some and for others there is a need to
communicate with many different people at different times. The different types of telephones we have
available in the unit will provide this service when it is required.
There are many tactical telephones that will accomplish this. Some of them are telephone sets TA-
312/PT, TA-341( )/TT, TA-838( )/TT, TA-954/TT, and DNVT TA-1035/U. Some or all of these
instruments may be in your unit.
In addition, there are different means of getting the signal from the telephone to the distant person.
Some will be connected through a switchboard, some will be connected through intermediate equipment
prior to a switchboard, and some will be multiplexed in an effort to reduce the number of wire lines that
must be put in to extend these instruments.
Within this subcourse, we are going to be discussing telephone installation and maintenance. We will
also be discussing some of the other equipment needed to get the signal from the telephone set to
wherever it must go. Where the wires are identified as green or brown it is recommended you color
them for your full and comprehensive understanding of the technical material.
PART A - TELEPHONE SET TA-312/PT
The TA-312/PT is an old telephone, but is very reliable and will provide many hours of
uninterrupted use when it is installed properly and not abused. We will be discussing characteristics,
installation, and operation.
The TA-312/PT is a 2-wire, battery-operated field telephone. It may be used in a simple point-to-
point voice frequency wire communication line or any 2-wire ringdown subscriber position of a
telephone communication system.