Teyleten Robot LM2596S LM2596 with LED Display Voltmeter Buck Converter DC-DC 4.0-40V to 1.25-37V 2A Voltage Adjustable Board Step Down Module Power Supply Module (5pcs)

At first I thought all five boards were bad. I adjusted the potentiomemters but the output voltage never changed. I connected an ohmmeter on the pots and saw they read about 2k ohms. I turned the the pot screw a thousand bazzilion times counter clock wise before the resistance changed. Once they are adjusted to 500ish ohms the output voltage was easily adjustable. Other than this they work as advertised and are a good little board. I like the voltage display so I don't have to dig out my voltmeter everytime I need to adjust it.

This item seems to work good I just received them and haven`t put them into use. I hooked them up to a 16v laptop power supply the input voltage showed 16.6 volts so the input readings are accurate. When setting the output voltage I was needing 12v,9v, and 5v to get a reading of 12 volts the output had to be turned down to 10.0 on the display. to get a 5 volt output the display reading had to be at 3.4 volts so make sure you use a voltmeter when setting the output or you might be burning you project up with too much voltage!!!!! As far as life of the converter in use time will tell, if I see they do not hold up I will be changing my review but so far they have a 5 star from me. I am amending my review the battery in my voltmeter was almost dead when I started setting these converters since replacing it these converters are within a few tenths of a volt when setting the output voltage so as long as they last in use I have to change my rating from a 4 star to a 5 star rating.

Packaging was really good!

First, this is a 4 star rating, if this fits your need I would recommend this product. I have tested the input and output display accuracy with a volt meter and they are accurate. In use testing powered a 12v tube hybrid preamp requiring a OEM 1A transformer, this DC to DC converter powered it just fine, ran for 3hrs with no problem. My only problem was the potentiometer used for setting the output voltage. It is soldered on crooked, and at an angle. There should be holes in the PCB that match up to legs on the pot to allow the POT to sit flush to the PCB and stabilize the pot from turning or moving. Or cut the bosses off the pot to allow to sit flush. The pot itself is difficult to turn, putting stress on the three pins soldered to the PCB. I had to hold the pot with my fingers while adjusting the output voltage, I was afraid it would rip the pot off the board or damage the traces.

The media could not be loaded. (GOOD) - When I got a board that worked, it was AWESOME. Was able to adjust the output voltage within ~0.6 volts of input.-- Display. The Voltage indicated on the LEDs measured remarkably close to the actual.--- The small push button on the board switches between INPUT and OUTPUT voltage(BAD) - Zero documentation and had to experiment(UGLY) - PARTS ACTUALLY OFF TWO BOARDS OUT OF THE BOX! A third, never powered up... good thing it came in a pack of 5 LOL!Unofficial Operating Instructions- Input vs Output voltage found experimentally to be within 0.6V I must stress this is only with two boards and its clear the manufacturing quality control is lacking so I would give yourself a wider margin in your design.- PowerUP. Would recommend starting at a high voltage (~15V) as it seems like the preset was 8V. The larger gap will allow you to easier see the power change- Display and LED. When you push the onboard button the display will cycle between input and output voltage. There is also two LEDs next to the button "IN" and "OUT" to indicate what voltage you are viewingWARNINGS - From other users reviews*** DON’T GO ABOVE 40V input --- OR BAD THINGS WILL HAPPEN*** ENSURE proper polarity for input voltage --- OR BAD THINGS WILL HAPPENHope this helps... short video provided to show what I have mentioned here... (EXCLUDING THE BAD THINGS HAPPENING)

I used these in a project car with custom electronics. I had a couple different voltage requirements, these are easy to set the voltage, and remain stable.

In fairness I have only had the opportunity so far to use one of the five buck converters. There wasn't really any documentation with them but there were plenty of YouTube videos showing how to set them up. Setup was a snap and I confirmed all my voltages were accurate using a Fluke multimeter. My only concern is this was tested using a steady input voltage of 17V generated from a 110V power adapter. Ultimately I will have this hooked up to Lithium Ion batteries and the input voltages will slowly drop with usage by a couple volts. I have concerns that the output voltage will also decline by an equal percentage. But only time will tell.

Ive got these running off terminal blocks to set voltage to various scenery lightsthis is perfect for handling scenery with various voltage requirementsi'll send 14 volts from an adjustable power supply to a terminal block, then come off the block terminals to bucks set for various voltageiE one buck is set to 3 volts to run a series of 3v lights. another buck is on another terminal set to 12v for a number of 12v lights. with a 2 amp output max, you can run a lot of lights off of one buck.power output is stable. no idea how long they will last, but they are solid and stable.