Fully compatible with existing VHF/UHF 2-way radio systems, Patriot Display Series 144/446/444D Portable and 110 Vac base station include 10 PC-programmable channels for 2-tone decode within 300-1,500 Hz. Dispatch selective calling options include group call, all call, automatic reset, and transpond alert. Standby mode is maintained until decoding. Large speaker, easily heard audio output, and channel scanning are included.