DollaTek PWM Signal Generator 1Hz~150KHz Dual Mode Generator Adjustable Pulse Frequency Duty Ratio Duty Rectangular Square Wave Module with Case

I use these for controlling telescope mounts when astro imaging, a precise, consistent yet controllable pulse train is required to match the speed of the telescope to the apparent motion of the stars. cheaper than buying a microcontroller, display and switches. I've got quite a few around the place, and none of them have ever played up.

Does what it says. Price is right for the function.

Although you can turn the output signal on/off using the 'On' button, there is no way to turn the whole unit, or even the display on/off from the unit's controls. You have to physically connect/disconnect the supply or incorporate a switch somewhere in the supply circuit.I found this out because I decided to install an internal Lithium battery, with a USB-C charge controller, so that I didn't have to hook it up to a seperate power supply every time I wanted to use it. It also makes it portable if required.The front screen is cheap plastic film and will be easily scratched.The connector block is very weak and will not grip stranded wires at all, that are less than about 0.5mm.Its frequency output is fairly accurate across its range. For example: When it states 10Khz on the display, I read 10,060 Khz on my oscilloscope. I could not find any inacuracy at all with the Duty Cycle.The output power is enough to illuminate a single LED, for visual confirmation purposes, but I wouldn't recommend trying to drive more than one low current LED, or any inductive loads without proper amplification.Overall a useful little unit for generating pulses up to 150Khz for testing, diagnosing and general experimenting for the price.

Excellent product

I used these modules before and they work well, with a clean PWM signal output - good frequency and duty cycle regulation

The item looks good but no instructions QR code not giving instruction but asks personal questions I want written instructions in English nothing else needed pleas dispatch these to me.

Not great tbh

I can't use it, no instructions, don't know what cables I need,or what they would do if idid know.It's going back