Maxmoral2pcs DC-DC Buck Converter Power Module 3A Adjustable Step-Down LM2596 Voltage Regulator 24V to 12V 5V 3V

Used this to step down a li-Ion battery pack to 3.05v for a wireless guitar pack that previously chewed through 2xAA batteries. Board is a little taller than I had hoped, but it still fit for my use case. Little light in the board even gave me good insight as to the charge state of the battery.

worked perfect to change the voltage for a PC Fan. 24 volts to 12 volts.

I think some of these are being returned due to poor instructions. I purchased these to run 12v fans on a 24v supply and so far the one is working great. (Haven't wired up the second yet). I'll come back and update this review if there's any issues or premature failure."After wire connection, first to turn a dozen times, then adjust the voltage by anticlockwise rotation."Sooooooo turn which direction a dozen times?I'm far from an electronics guru and this took me a bit to figure out based off other reviews so hopefully this helps.Turning clockwise - increases output voltageTurning counter/anti-clockwise - decreases output voltageThere's a LOT of adjustment in the potentiometer that simply will do nothing. Ignore the instructions - if you fire it up and the output voltage is the same as your supply, just keep turning counter clockwise until it starts going down. If you hear a clicking sound coming from the potentiometer it means it's bottomed out (try not to do this I'm guessing it's bad for it). I finally figured this out after cranking it counter clockwise for what felt like 40 turns and it started clicking. Then noticed my output voltage finally changed from 23.3 to basically zero.

I bought this product for use on some older electric trains I work on. Wanted to get a consistent voltage to my train lights (led) and accessory motors, from the track power which is variable. Out of the package and using jumper wires, I had the unit attached to my variable DC power supply. A few turns of he pot and I had consistent 3V output from 3 to 20 volts input. Small enough I can fit it almost anywhere, including some of the smaller HO trains I work on. Great value for the price!

I thought that there was a problem with the power module at first, as I couldn't get the output to change. I finally figured out that the potentiometer had to be turned a number of turns 15+ before the output voltage started to change.I have a 24VDC supply, and I have power module set to 5.00 VDC. After I connected my Raspberry Pi, I rechecked the voltage under load and it still measured 5.00VDC. I was very please to see that the voltage did not change under load.I have been using it for 1 month with no issues. I would buy it again.

Allowed me to step down a 24v power source to 10v for a fan I was installing. It's quieter now and I can run a more modern fan in my old printer.

Whatever voltage I put in, I got out. No matter how I adjusted the resistor. I verified everything was hooked up in the correct in/out according to the printed circuit board. As MANY others have said, they are just junk. No quality checks, just mass-produced and sent out because they would rather WASTE your time and money than spend a little of their time and money making a quality product. Amazon should support 0 star reviews.

Used this to drop the voltage down from 24VDC to 12VDC for fans in a 3d printer. Both units have been working for over a year.