10KHZ TO 220MHZ WORKING RANGE: Working range is 10kHz to 220MHz, can be used with for Pro Mini. Use general 128×64 I2C for OLED for display and Si5351 module. Radio Transceiver, SDR QRP HF Transceiver 10kHz to 220MHz VFO Generator Superheterodyne Receiver with Bar Graph Indicator, High Stability HAM Variable Frequency Oscillator.