12-3. Communications System Description. This system consists of the methods of communication described below:
12-3.1. Radio communications equipment. This equipment, located in the barge dayroom and cabin of the workboat,
consists of the type AN/VRC-46 High Frequency (HF) Frequency Modulation (FM) Army issue radio (hereafter called the
HF/FM Army radio), a Very High Frequency/Frequency Modulation (VHF/FM) commercial marine radio, and Ultra High
Frequency (UHF) FM handheld walkie-talkie transceivers.
12-3.2 Army radio. The HF/FM Army radio provides communications with other stations equipped with radio
frequencies reserved for military (primarily US Army) use. This radio enables the barge to communicate with its towing
vessel, other military support vessels, military shore-based radio stations, and military aircraft. Transmission distance is
normally 25 miles or less.
12-3.3 Commercial marine radios. These provide VHF/FM radio communications between workboat and barge and
between workboat or barge and other vessels equipped with radios working these same channel frequencies.
Transmission distance is normally 25 miles or less.
12-3.4 Walkie-talkies. These preset, crystal-controlled, hand-held, nickel cadmium (ni-cad) battery-powered portable
radios can be preset to the same frequencies available on commercial marine radio channels. They provide VHF/FM
communications between crew personnel onboard, between shore and crew personnel, and between crew personnel on
workboat and barge. Transmission distance is normally 5 miles or less.
12-3.5 Foghorn equipment. This equipment sounds the foghorn to warn oncoming vessels of barge location during
12-3.6 Telephone system. This system provides intercommunications between dayroom system operator and
crewmembers at any telephone station on the barge. Telephone stations provide jack receptacles for connecting a
headset. By using dayroom telephone equipment, operator can page and communicate with personnel at any telephone
station. When on line with operator, crewmembers at telephone stations can communicate with operator or
crewmembers plugged into other stations.