Feature: 1. Large Range: The working range of this VFO is 10kHz to 220MHz, with 0.5PPM high precise TCXO clock, the frequency change is more accurate. 2. Bar Graph Indicator: With bar graph indicator for signal strength and 20 band presets, can also be used as RF or clock generator. 3. 2 Wire Connection: Support I2C data transmission, only need 2 wires to connect the display screen or Si5351, very convenient for connection. 4. High Stability and Accuracy: The frequency generation of the VFO meter has high stability and accuracy, simple and effective. 5. Excellent Material: Made of precise wiring PCB board, stainless steel and aluminum shell, has long last durability for long term usage. Specification: Item Type: Variable Frequency Oscillator Material: PCB, Stainless Steel, Aluminum Shell Operating Range: 10kHz to 220MHz Power Supply Mode: 3.7V 1000mAh polymer lithium battery (built in) FM Mode: 1. Rotate Encoder Knob: Adjust the volume or frequency. When the encoder is rotated at the beginning, the knob can adjust the volume, press the encoder once, the knob can adjust the frequency. 2. FM: When the page is in AM mode, press the FM button once, the page becomes FM mode. 3. BWF: Bandwidth, press the button to change the size of the bandwidth, there are five options: AUTO, 40 K, 60K, 84K, 110K. 4. AM: When the page is in FM mode, press the AM button once, the page changes to AM mode. When the page is in AM mode, short press the AM button to increase the frequency, long press the AM button to decrease the frequency. 5. SAV: Short press to change the size of TS (step frequency), there are five gears: 0.1MHz, 1MHz, 2MHz, 5MHz, 10MHz. Long press to save the changed TS (step frequency). AM Mode: 1. Rotate Encoder Knob: Adjust the volume or frequency. When the encoder is rotated at the beginning, the knob can adjust the volume, press the encoder once, the knob can adjust the frequency. 2. FM: When the page is in AM mode, press the FM button once, the page becomes FM mode. 3. BWF: Bandwidth, press the button to change the size of the bandwidth, there are five options: 0.1K, 1K, 2K, 5K, 10K. 4. AM: When the page is in FM mode, press the AM button once, the page changes to AM mode. When the page is in AM mode, short press the AM button to increase the frequency, long press the AM button to decrease the frequency. 5. SAV: Short press to change the size of TS (step frequency), there are four gears: 1KMHz, 5KMHz, 10KMHz, 100KMHz. Long press to save the changed TS (step frequency).. Package List: 1 x Variable Frequency Oscillator1 x Antenna1 x USB Cable