VCO Explained - What is a Voltage Controlled Oscillator?
A Voltage Controlled Oscillator (VCO) is an electronic oscillator whose oscillation frequency is controlled by a voltage input.
The AD9850 DDS Signal Generator Module provides 0-40MHz sine and square waves. It is equipped with a powerful 125Mhz Oscillator and excellent for a signal generator and oscilloscope based DIY projects.