c. a sound-powered telephone.
d. a common-battery-signaling telephone.
8. Telephone Set TA-312/PT may be operated in emergencies without batteries. This type of operation
utilizes the receiver as a sound-powered transmitter and will provide communication for a maximum distance of
approximately
a. 6.41 km (4 mi).
b. 12.88 km (8 mi).
c. 19.32 km (12 mi).
d. 25.56 km (16 mi).
9. Repair and maintenance of Telephone Set TA-312/PT is a function of direct support and general support
maintenance. However, the organizational maintenance man is permitted to
a. apply moisture and fungus-proofing.
b. repair any breaks in internal wiring.
c. replace or adjust the handset retaining springs.
SPECIAL NOTE
To perform maintenance and repair on Telephone Set TA-312/PT, or any communication equipment, requires
a thorough knowledge of the equipment and a complete understanding and interpretation of schematic and wiring
diagrams of the equipment. Figure 5-1 of TM 11-5805-201-35 will be very helpful in solving the remaining
exercises of the lesson.
10. Switches in figure 5-1 are labeled S. Switch S4 can be identified as the
a. hookswitch.
c. INT-EXT switch.
b. handset .switch
d. selector Switch.
11. When the TA-312/PT is connected for common-battery use, a dc path through the telephone will signal
the switchboard. If the switchboard receives a signal when hookswitch S2 is open, the probable trouble is
a. a short through the buzzer.
b. a short through capacitor P1.
c. an open at the terminal board.
410 L3
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