Do not crank or ring the field telephone because damage could occur to the AM-1780
and/or the entire AN/VIC-1 system.
1. If one or more of the control boxes becomes inoperable but the AM-1780 is still
operational, install TA-312 or TA-1 field telephones at the station(s) where the bad
control boxes are located and run field telephone wire back to the AM-1780. The WD-
l/TT should be hooked upon the "line" jacks of the AM-1780.
2. If the AM-1780 is not operational, replace the entire intercom system with TA-312
or TA-1 telephones and field telephone wire. Run the wire in a circle throughout the
vehicle so that all telephones are connected to the same wire.
3. Record the BDAR action taken. When the mission is completed, as soon as
practicable, repair vehicle using standard maintenance procedures.