Hi guys here I have a Vietnam war era M1 that is fitted with a AN/PRR-9 helmet receiver. The receiver also comes with it’s AN/PRT-4 transmitter both receiver and transmitter have contract numbers which date them to 1967. From what I have read about these radio sets, the PRT-4 and PRR-9 worked together as an attempt at a simple, lightweight Squad radio, albeit one-way. First fielded in Vietnam by the U.S. Army in March 1967, the idea was to extend an infantry platoon and/or squad leaders’ command and control beyond verbal, hand signals and personal contact communications. They cost around $1100 per set in 1967 which in today’s money would be a hell a lot :shok_yikes: They were apparently not liked by the troops in Vietnam as they broke down a lot due to rainy and atmospheric conditions. Troops tended not to wear the receiver on the helmet and wore them on their uniform.
The helmet is manufactured by Ingersol with the heat stamp of 1-6214 and produced from 1966 to 1967. The liner has a production date of 31 MAY 1967 and is marked in the crown M 30 and stamped on the webbing in black ink the number 30 which identifies it as a MARMAC made liner. The Mitchell cover has the contract details that date it to late 1964 to early 1965.
Thanks for looking guys cool militaria

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