Features: 1. This is a 1.2GHz frequency meter, and all settings are automatically saved and can be called directly upon startup. 2. The frequency reference adopts a temperature compensated voltage controlled crystal oscillator (2.5 ppm VC-TCXO). 3. Adopting a unique gate control method and precise time algorithm (non timed interrupt mode). 4. The gate (display refresh) time is optional at 0.01 seconds/0.1 seconds/1.0 seconds, and the frequency value is displayed in real-time. 5. Single ended input design, with three optional frequency measurement channels (low channel/high channel/automatic channel). 8. Invalid zero automatic blanking, invalid frequency value display filtering optional, and last digit blanking optional. 9. The circuit is simple, the structure is reasonable, the dual button control is easy to operate. Parameter: 1. Gate time *0.01 seconds *0.10 seconds *1.0 second 2. Measurement channel (both high and low channels have high resistance) *Low channel Measurement range: 0.1 MHz~60 MHz Measurement accuracy: ± 100Hz (at 0.01 second gate) ± 10Hz (0.1 seconds at gate) ± 1Hz (at 1.0-second gate) Low channel sensitivity: 0.1 MHz~10 MHz: better than 60mVPP 10 MHz~60 MHz: better than 60mVPP 60 MHz~75 MHz: untested *High channel (64 frequency division) Measurement range: 20 MHz~1.2 GHz Measurement accuracy: ± 6400Hz (at 0.01 second gate time) ± 640Hz (0.1 seconds at gate) ± 64Hz (at 1.0-second gate) High channel sensitivity: 20 MHz~30 MHz: better than 100mVPP 30 MHz~60 MHz: better than 50mVPP 60 MHz~2.4GHz: untested *Automatic channel: Automatically select high or low channels based on the input signal frequency, with a recognition frequency of 60 MHz. If the amplitude of the input signal greater than 60 MHz is insufficient to automatically select the high channel, the high channel should be manually selected for frequency measurement. 3. Intermediate frequency setting: Independent dual intermediate frequency design, with a minimum intermediate frequency adjustment step of 100 Hz and an intermediate frequency range of 0~99.9999 MHz. It can be set to add or subtract intermediate frequency mode. 4. Frequency reference: Using a 5032 package 13.000MHz temperature compensated voltage controlled crystal oscillator (VC-TCXO) with a frequency stability of ± 2.5 ppm. 5. Working voltage: DC input: DC 9V~15V (with power polarity reverse protection) 7. Display digits: Eight digit LED display, with a maximum display of eight digits. 9. Dimensions: Length x Width x Height: 125.5 mm x 25.5 mm x 21.5 mm 10. Onboard interface DC IN (power interface): HX2.54-2P socket RF IN (signal input): HX2.54-2P socket ICSP (Programming Interface): 2.54-6P pins Package include: 1* module 2 *rays