Review on 🔌 10pcs MakerHawk LM2596 DC-DC Buck Converter: High Efficiency Step Down Voltage Regulator, 3.2-46V to 1.25-35V, 3A Adjustable Power Supply Module by Cameron Chandra

I used a very good desktop power supply and no matter what voltage I put in the device (I tried from 5V to 30V) the output voltage only dropped to 3.5 to regulate 4.1 V. Then I opened and tested three more with the same result. I looked at the datasheet and found that there is a voltage divider element that sets the output voltage, so I started researching things and they didn't match. I unsoldered an adjustable trimmer and underneath was a small SMD resistor between two legs. I removed that resistor and re-soldered the trimmer and now it works correctly i.e. I can adjust the output voltage anywhere between 2V and a little less than the input voltage. I'm not sure if what I did was a "fix" but I think whatever works (I didn't want to fully reverse engineer the entire board). Other reviews are positive and I've seen videos of this board working. connected for a similar test, and everything worked fine on the video. So maybe it was just a bad batch with the wrong components? In any case I wouldn't buy this board unless you know they fixed the problem. I would send it back but I don't know if I can or not at the moment even though the boards are defective. At least they weren't expensive.