Description: Used as a square wave signal generator produces a square wave signal for the experimental development use A square wave signal is used to produce a stepper motor-driven drive Produce the adjustable pulse for MCU use Generates the adjustable pulse to control the associated circuits Made of high quality material, durable and practical Specification: Input voltage: 5V-12VDC. Input current: ≥ 100mA 5. The frequency adjustment range: 0.07HZ-2KHZ (also cycle in about 0.45ms to 15s). 6. Duty cycle adjustment range: 0% to 100% (High / cycle). Size Chart: 1. The board has four the shorting can select the frequency. 2. Inserted 0 short-circuit , the longest cycle upwards to 0.3 s. 3. Inserted short-circuit , the longest cycle can be adjusted to about 4s. 4. Inserted two short-circuit , the longest cycle can be adjusted to about 7s. 5. Inserted three short-circuit , the longest cycle can be adjusted to about 10s. 6. Inserted four short-circuit , the longest cycle can be adjusted to about 15s. 7. Duty cycle adjustment range: 0% to 100% (High / cycle). 8. Output Current: strip 9012 transistor drive capability is strong, about 500MA output current, the output can directly drive small relays or small motors. Package Includes:(8 Pack) 1 Piece Pulse Module Frequency Adjustable Module Square Wave