Vietnam War Era RT-196/PRC-6 Radio Receiver Transmitter Walkie Talkie. The AN/PRC-6 is a walkie-talkie used by the U.S. military in the late Korean War era through the Vietnam War. Raytheon developed the RT-196/PRC-6 following World War II as a replacement for the SCR-536 handy-talkie. The AN/PRC-6 operates using wide-band FM on a single crystal controlled frequency in the 47 to 55.4 MHz low band VHF band. Rated power output is about 250 mW. The range is about one mile (1.5 km), but much less in the jungle.