MT3608 DC-DC Step Up Boost Power Converter - 2A Module, Adjustable Step Up Voltage Regulator Board - 2-24V to 5V-28V Output Voltage (Pack of 10)

I received 10 boards and tested 1 of them and did not work with 4.1v input. No change in output voltage regardless of potentiometer. Tried two more boards and they are the same. The boards should work with greater than 2v but did not work. I am returning them no point of checking remaining 7 boards.After further testing none of the boards are defective. The issue is that you need to turn potentiometer at least 20~30 turns all the way both sides and at one point output voltage will increase. Turn until u hear click sound. If no change then turn opposite direction and it should work but many turns in that direction.

Two of these failed immediately. Other two worked for a while. I am using 2 of them simultaneously for two circuits up-converting from 12V to 24V, powering a 16W circuit. But both of them failed within a few hours of use. The failure resulted in them producing only the input voltage at the output. I am on the last one (of the 5-pack) and I expect it to fail as well. Very unpleasantly surprised. Actually heavily disappointed. I removed 1 star for each failed board from the 5-pack.The ad says that these up-converters work with loads up to 2 amps. I am using them only for 0.7A each so they should be able to handle that just fine. But they do not. I requested a replacement package, foolishly hoping that another batch might work better. I will post an update once I test them out.Though I should not fail to provide more details about the up-converters. They come with nice pre-drilled solder pads, they are big enough for bigger wires for 2 amps, that is a nice touch. The adjustment trim-pot is pretty funky, the quality really is not good because when it is turned maybe 1/4 turn, the voltage barely changes, then it is just barely touched and now the output voltage jumps an extra volt. The trim-pot operation simply is not smooth enough for fine adjustments. Otherwise, once the trim-pot is adjusted, the board holds the output voltage well, no big deviations, maybe a tenth of a volt but that's also the reading error on my DMM so it's hard to tell. Size of the boards is acceptable and as advertised. If I ever get any that will actually stay working, I will slide them into a 1.5" heat shrink sleeve for protection.As far as the refund goes, I have been waiting almost a month. I have neither the boards, nor my money. On the product returns page, Amazon indicates when I should receive the refund. Whenever the date comes up, they move it out. The return page shows "Refund issuance is delayed". No explanation. Amazon is pretty good about issuing a refund once they receive the merchandise but they've had the boards 2 weeks and no refund. I wonder about their actual procedural policy and why the process is stuck. Disappointed on this front as well.

HelloI purchased the MT3806 so I could boost my 9v to 11volts DC. My intended use was for raising the voltage of an original Made In Japan CE-2 guitar pedal.My first thought was that the MT3806 was small enough that it could easily be hidden, and I could use heat shrink on it to hide it.My first attempt to use the MT3806 was a failure, it literally sparked, burnt and caught on fire when I turned on the power.On guitar pedals the Center is Center Negative so I reversed the VIN- and VIN+. After that it started working but the voltage did not change at all.I returned to Amazon and read the reviews and started with another brand NEW MT3806. The great part is they are very affordable(cheap) and it doesn’t hurt my wallet to try again. I tightened until the thread ran out and clicked(no voltage change). After that I began to lefty loosen the Screw type potentiometer. It took a long time but it worked towards the end of the screws thread.I was able to regulate the output voltage to 10.76vDC from an input of 9vDC. Of course I do think and I also know that I don’t intend to use a load greater than 30mA.Worked out great, no issues, no noise issues either in an audio device.

These things are easy to destroy by accident. I applied 7v on my first one right out of the box and definitely destroyed it. They are really finicky and the processes for adjusting them is very specific. While the first was my own fault, I watched a tutorial after and I still couldn't get 2 of them to work. That left me down three out of the ten. Still enough for what I needed and price and shipping time were very good which is why I decided to give it four stars instead of three. I am just a little disappointed that two seemed DoA.First, you have to apply a load (use a meter or voltage display module) and 3v DC in. These things are calibrated to the lowest possible value out of the box and exceeding the minimum voltage by a volt or two can ruin them. Rotate the adjustment pot counter clockwise until you see a voltage increase. This can take half a dozen to a dozen rotations. Adjust until the output reaches the target voltage you have in mind for your product. Once you have it set, disconnect it from the 3v power supply. It's now safe to connect any supply (that I assume doesn't match or exceed the Vout) you set and changing it after seems to work fine. When doing the initial setup, I found sometimes be as little as .1v under or .2v over seemed to prevent the calibration logic from kicking in. Once the logic kicks in for the first time, adjusting it is easy.