The module can output sine wave and square wave, 2 sine wave and 2 square wave output. AD9851: 0-70MHz After the frequency is 20-30MHz, the harmonic becomes larger and larger, and the waveform will become more and more unclean. Square wave: 0-1MHz Uses a 70MHz low-pass filter to make the waveform's SN ratio better 10-bit DAC, 32-bit frequency control word The comparator's reference input voltage is generated by a variable resistor. Adjusting this resistor can get different duty cycle square waves. Note: In the case of outputting a sine wave, connect to the IO port of the square wave output and directly adjust The blue potentiometer can output a square wave. AD9851 module uses 30MHZ active crystal Colour:As Shown Material:PCB Package Contents: 1 x Signal Generator Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.