DROK Frequency Generator, DC 3.3V-30V 5-30mA 1Hz-150kHz Adjustable Output PWM Pulse Duty Cycle Square Wave Function Signal Generator Module

Works well for teaching frequency and PWM on demo boards.

Works great. If i had to complain about anything, it doesnt allow for inverting the signal so youre stuck with a PWM+ output signal but thats not a big deal. The duty cycle is just reversed meaning, a 10% minumum 90% maximum required signal would be 90% minimum, 10% max when requiring PWM-. I have used this to test automotive fuel pump controllers and fan controllers that use a variable input PWM signal to vary speed of the fan/pump. The frequency adjustment makes it easy to determine the appropriate frequency range for the modules. The pwm output is accurate, verified with an oscilloscope. Ive used it to test and control Infinity fan controllers, Ford fuel pump driver modules (fpdm) and Dodge fuel pump control modules (fpcm) without issue.

Wet small and simple thing

I bought this controller to drive the 12V brushless fan. It works as spec. very easy to wiring and installation. the knob is a plus because it makes the adjustment much smooth and easy. I don't like to button style.

I didn't work at all thought it was defective so I had it replace with the same thing. It came in damaged like it was stepped on before they packaged it. Do not buy

Great little unit! Worked exactly like I needed it to. I bought it to test a pierburg cwa pump. Powered the unit with the power and ground going to the pump and sent the pwm signal out to the pwm input on the pump. Set it to 150hz and slowly ramped up the duty cycle. Bam! Action!

The user interface took a little time to master, but it's intuitive once you have spent a a few minutes on it. The higher accuracy mode (0.1% steps) worked well with the motor I used that required very-low RPM values (0.1% to 2.9% settings). Also good that the box retains the last setting prior to power off and and back on. I'll design something that has higher accuracy for my final product, but this was great for my customer demo and lab testing.

excelente.....muchas gracias.

El vendedor cumplio lo comprometido en su oferta y el elemento electronico esta funcionando correctamente, de igual forma fue entregado muy en tiempo.

Very easy to use device

Worked as described, set to 128Hz and produced 127Hz with a 5V feed wire. Used on electronically controlled alternator, works perfect for setting voltage via duty cycle. 10/10 would buy again.

The case of it was broken when showed up but still worked and did its job of testing gauges on Volkswagen gauge cluster.

This frequency generator is very poor quality. The plastic screen sheild keeps falling out of place, it has lamination issues also so it looks really ugly, and the programming is impossible, the functions don't work as described in the photos online, mind you there are no instructions and the online instruction is so poor that it might as well be written in Chinese.