CHAPTER 1 INTRODUCTION
1-1 Purpose. This Technical Manual (TM) describes the operation and maintenance of the communications system on
Water Purification Barges. Information on other systems Installed onboard is in TM 55193020914P-1 thru P-11 and P-13
thru P-18. TM 55-1930-209-14P-18 and TM 55-1930-209-14&P-20 contain appendices common to all TM's. Location of
major barge components is shown in Figure 1-2
1-2 Scope. The communications system consists of three separate communications methods. These include radio
communications equipment, foghorn, and Intercom telephones, which are briefly described as follows Details are In
Chapters 2 thru 4.
1-2.1 Radio communications equipment. This equipment, located In the barge dayroom and cabin of the workboat,
consists of a type ANNRC-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
1-2.1.1 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.
1-2.1.2 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
1-2.1.3 Walkie-talkies. These preset, crystal-controlled, hand-held, nickel cadmium (n-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
Under U.S. Federal Communications Commission (FCC) regulations, commercial marine ship
radio and walkie-talkie stations, operating in U.S. and adjacent waters, are primarily reserved for
safety of life and property. Therefore, distress and safety communications have absolute priority.
Those frequencies not reserved for calling, distress or other safety purposes, however, may be
used for radio telephone calls to coast stations or between ships. Operation of radios using
military frequencies is controlled by Army Standard Signal Instructions (SSI) and Signal Operating
Instructions (SOI). Extracts of necessary portions of these documents are obtained from Army
unit to which the barge is attached or assigned.
1-2.2 Foghorn equipment. This equipment sounds the foghorn to warn oncoming vessels of barge location during poor
1-2.3 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
1-3 Warranties and guarantees. Manufacturers' warranty/guarantee information is in Section VII In Chapters 2 thru 4
1-4 Maintenance forms and records. These are explained in DA PAM 738750, The Army Maintenance Management
1-5 Destruction of Army materiel to prevent enemy use. This shall be as directed In TM 750-244-3
1-6 Storage. For storage of this equipment, refer to Section V in Chapters 2 thru 4