I came across the North Shore Emergency Association's website recently and found their club history page interesting: nsea.com/nseainfo.htm This link briefly discusses how the "travel tone" of 141.3 Hz and the national calling/emergency frequency of 462.675 MHz came to be. NSEA was one of the very first adopters of GMRS in the early 1970s, then … Continue reading The history behind 462.675 MHz and the travel tone