Anysecu SF401 Plus 27Mhz-3000Mhz Radio Portable Frequency Counter meter with CTCCSS/DCS Decoder The frequency meter capable of measuring the parameters of the frequency of the continuous carrier signal walkie-talkies , with signal strength indicator. it is the tool of choice for maintenance personnel,test frequency and signal strength of wireless enthusiasts. This portable frequency counter is designed for counting continuous wave signal comes from Two-way Radio. There are easy ranges for you to choose. The ranges cover most of the frequency of the two way radios you want to measure. Its four-button control is easy to use and its small size allows you to carry it anywhere you like. Work by TCXO(Temperature Compensate X'tal (crystal) Oscillator) ,In the range of -45 C ~ 65 C can reach  2 ~  4ppm accuracy