SF401 Plus Portable Handheld Frequency Counter for Walkie Talkie, Frequency: 27MHz-3000MHz 1. The frequency meter capable of measuring the parameters of the frequency of the continuous carrier signal walkie-talkies, with signal strength indicator. 2. This portable frequency counter is designed for counting continuous wave signal comes from two-way radio. 3. There are easy ranges for you to choose. The ranges cover most of the frequency of the two way radios you want to measure. 4. 4 buttons for all function control, its four-button control is easy to use and its small size allows you to carry it anywhere you like. 5. Work by TCXO (crystal) Osc.2~2.5ppm. 6. Use for VHFUHF walkie-talkies. 7. Auto power off 1-9 minutes. 8. Frequency response time: 0.2-0.5s (CTCSSCDCSS>0.5-1s). 9. 240*320 pixel color LCD. 10. Digital select digi0.000 or 0.0000. 11. Frequency range: 27MHz-3000MHz (Note: 27-100MHz, it can not be guaranteed and the corresponding normal emission appliance)