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.

Used these for Daughter's high school physics project. powered by 9V battery, set up 3 circuits to power 1.5V Christmas light bulbs. One Circuit had 2 of these bulbs, which needs max 6V power supply, while the other two circuits with one bulb need 1.5V. These modern resistors are adjustable with a small flat screwdriver to supply the exact Voltage needed for the circuit. Can be utilized for other, more sophisticated projects. Recommend this product.

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.

I used the to install a 12v fan on my Ender 3 Neo which has a 24v output for the stock fans. Simply put, it turns the 24v into 12v as to not damage the aftermarket Noctua fans. It has digital display that shows voltage in and voltage out so you know exactly what’s going on.

(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 viewing WARNINGS - 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 HAPPEN Hope this helps... short video provided to show what I have mentioned here... (EXCLUDING THE BAD THINGS HAPPENING)

Packaging was really good!

I love these modules. I got two yesterday and I’ve found uses for them already. I’m using one to step down the voltage for my 3D printer’s power supply to power some fans, works like a charm. I found the new fans weren’t cooling quite as efficiently as the fans they replaced, so I simply bumped the voltage up a little and it works great. I’m using the other one to undervolt some 24V LEDs that I bought to light up my workspace. I broke the remote that came with it, and I don’t have anything on hand that can PWM 24 volts, so I have no choice but to run all of the channels at max brightness. A cheap analog solution to a digital problem 😂

4 of the 5 didn't work. The one that did is not worth the risk of hooking up to my expensive electronics