A Troop 4/12th Cav

Who We Were
Why Now
Join Commo Net
A Troop Lineage
Troop Roster
Message Board
Tools of the Trade
Rank & MOS
Jargon & Slang
Photo Albums
The Cav Store
412 Troopers Home
A Troop Reflections on the Commo Net

Materials contributed by: Keith Eaton, Coop

Communications Network

Artillery was called in by our FO or Forward Observer. The Troop usually had 1 Lt and 1 Sgt as FO's . They used the Radio to call in our support. Typically they used their own frequencies and handled all contact with their people. I think they used a PRC 25 radio.

Log run requests came through the Troop TOC or Tactical Operations Center. Photo on right shows TOC at LZ Nancy and photo below is the First Sgt and Senior RTO at Cua Viet in the mobile TOC Alpha Deuce. The TOC would route the requests for parts , supplies , food to the different support areas in our Base Camp either at LZ Nancy or at Quang Tri Combat Base starting in late 1970.

mobile net
Each Platoon Leader and the Captain carried maps of our AO they would determine their location from these maps and radio the coordinates back to the TOC so we could keep track of where they were in case we needed to provide any support. The TOC also monitored the traffic on the Troop net and kept a record of all activity that was going on in the field. This information was forwarded to the Orderly room for the use of the CO if he was in the base camp or to the First Sgt while the CO was in the field.

The TOC also coordinated the calling of all medivacs; we would pass information to the choppers from the field until the choppers approched the troop; at that time the CO, then the Platoon Leader or Radio Operator on site would take over the final approch and pick-up.

We usually had two radios on the air at all times, one for the primary freq and a second radio to monitor a secondary freq or to monitor the 1/77 Armor freq when we reported to them. Radio Jargon

The Commo Section also provided all repairs for Troop Radio equipment; we had a repair shop on site. We also maintained the troop Generators... Allen Anderson kept them running smoothly.

FM voice radios provided the primary means of communication for cavalry units in Vietnam. These units provided short range, two-way frequency modulated (FM), radiotelephone communication between vehicles.

RT-256/VRC and RT-524/VRC

These FM receiver-transmitters have essentially the same operational capabilities, the exceptions being that the RT-246 has a 10 preset channel capability and the RT-254 has no presets, but does have a built-in speaker.

Frequency range: 30.00 - 78.95 MHz Type of service: Voice Preset frequencies: 10 (RT-246 only) Transmission planning range: 20 miles stationary / 15 miles moving Type of operation: Push to talk Type of control: Local or remote Antenna: Center fed whip Number of channels: 920 Type of squelch: Noise or tone Power requirements: Vehicular 24-volt DC / Fixed 115/230-volt AC for Power Supply PP-2953/U

FM radio receiver R-442/VRC is used in conjunction with the Receiver-transmitter RT-246 and RT-524, giving the RTO a facility for monitoring an additional frequency.

Frequency range: 30.00-75.95 MHz Type of service: Voice Preset frequencies: none Antenna: Multi section whip Type of squelch: Noise or tone Power requirements: Vehicular 24-volt DC

AN/PRC-25 is the portable, man-packed radio set; AN/PRC-53 provides vehicular operation and AN/GRC-125 is capable of both man-packed portable or vehicular operation. Jargon: PRC25 was know as "PRICK25" by the troopers.

Frequency range: 30.00 - 75.95 Type of service: Voice Presets: Two Range: 5 miles Type of operation: Push to talk Type of control: Local or remote (using AN/GRA-39) Types of antennas: AN/PRC-25 short antenna (3' semi-rigid steel tape) - long antenna (10' multi section whip) AN/VRC-53 and AN/GRC-125 vehicular mounted AT-912 (10' vehicular whip with antenna matching unit MX-2788/VRC or MX-6707/VRC).

Number of channels: 920 Type of squelch: Tone operated Power requirements: Battery BA-386 / Vehicular 24-volt DC

SOI Signal Operations Index (frequencies, flare colors, etc.)



Radio Set AN/VRC53

Site Administrator      Other Links

This site is in no way connected to, or sanctioned by, any official Army or Government entity. This is, and will be a work in progress; we apologize now for any errors and/or mistakes. Information for this site has been and will continue to be gathered from many different sources. It is intended as a place for fellow troopers, family and friends of A Troop 4th Squadron 12th Cavalry (Vietnam Era) to visit, seek contact with, gather information or some insight into the history, language and jargon of the people who were part of A Troop, then and now. A Troop 4/12 Cav (Vietnam Era) invites and encourages trooper's family members to participate in the troop's reunions, memorial services, remembrances of our fellow troopers who have passed on to Fiddler's Green, and to continue the camaraderie of the BROTHERHOOD....Long Live the Cav and its BROTHERHOOD!!