I tried finding Hidden Gems on AliExpress AGAIN! (Part 4)

Here is the rewritten text in a well-structured article format:

**Unboxing and First Impression: Lab Bench Power Supply Boards**

As an electronics enthusiast, I was excited to unbox and test three lab bench power supply boards that I had purchased from online retailers. The first board caught my attention due to its ability to function as a UPS (Uninterruptible Power Supply). However, after conducting some experiments, I discovered that it had some serious flaws.

The board in question is a 18650 Lithium-Ion cell-based power supply with a USB-C port and a 5V output. At first glance, it seemed to work perfectly fine, as it was able to charge the batteries correctly and provide power to a load such as a media player even when the input power disconnected. However, things took a turn for the worse when I hooked up my oscilloscope to measure the output voltage.

**A Big Surprise: High Noise Levels**

I was shocked to see how much noise the claimed 5V DC output came with. In fact, it was more like a function generator than a proper power supply. The same problem applied to the 12V board I also received, which had a 5-star rating on AliExpress. This boost converter design clearly has some serious issues that I would not recommend.

**A Cheap Alternative: Lab Bench Power Supply with Display**

On the other hand, my second purchase was a small power supply board with display that only cost me around €25. It is super cheap considering it can output 1200W, which is more than any of my other lab bench power supplies. As a first test, I hooked up a 24V power supply to its input and played around with the knob and display to find out that I can easily set a current and voltage limit.

**Accurate Voltage and Current Limits**

I was pleasantly surprised to see that the voltage output and current limit values seem to be accurate. Even after pushing this thing close to its limit with a current flow of 15A, it only heated up slightly, nice. I also measured some input and output power values to create an efficiency graph, which told us for example that with a 12V output voltage we get an efficiency of above 90%, not bad.

**Conclusion**

After playing around with this thing quite a bit more, I was actually pleasantly surprised and the only complaint so far was that the input fuse is weirdly positioned. However, there was still a big problem with the output voltage and the occurring noise. As a comparison here is the noise of a proper lab bench power supply, they are worlds apart.

Even though this small power supply does offer a lot for its low price, I would not fully recommend it after seeing its output voltage; but you do you and maybe give it a shot anyway.

WEBVTTKind: captionsLanguage: enSometimes in life you buy yourself an AliExpress product with a 5 star rating,  only to find out that it performs terribly.But that is why this video series exists  in which I test all kinds of AliExpress products to tell you whether you should  check them out or simply ignore them.And in case you are completely confused  right now: AliExpress is an online shop based in China where you can not only get the newest,  weirdest and sometimes super useful products; but also lots of garbage. And today I got another 8 promising looking products to test; so let's not waste anymore  time and let's get started!INTRO This video is sponsored by Rohde und Schwarz. Now as you might know I love my  Keysight test gear, but as an engineering graduate I have worked with all kinds of  different brands and let me tell you that Rohde und Schwarz makes some awesome test gear as well.  In fact you might spot it in future episodes. But I am not here today to promote that;  Instead I want to tell you about their test and measurement YouTube playlist where you can find  150 videos about simple but also super advanced topics; broken down in helpful sub categories.  So if you ever had any unsolved questions while measuring, feel free to check it out.Let's start off with a special LED strip I got myself 2m of for around 16€. Now when it comes to LED strips I thought I have seen it all and by that I mean we got our dumb  single colour or multi colour LED strips whose LED brightness you can only control all together;  and then you got your addressable LED strips where you can control  each LED individually because each one comes with its own control IC. But this new LED strip from AliExpress is something I have not yet seen before  and the big obvious difference here is that the LEDs are encapsulated in a silicone like line. That of course diffuses the emitted light a lot better in comparison to normal LED strips. I would still say it is not perfect, but I think for many applications  you would not need an extra diffuser system.I was also excited to see that it apparently  features 630 LEDs per meter which is a lot more than the densest LED strip I got laying around. And after peeling off the silicone line, I can actually confirm this number; even though their  way of counting is a bit confusing.But since they use rather tiny LEDs,  the maximum light output of them is quite a bit lower than more traditional LED  strips which is also noticeable when looking at their power consumption. And last but not least as you might already have noticed this LED strip  also comes with ICs meaning you can control the RGB Colour for every 7cm of the strip. That is way less resolution than other addressable LED strips though and worst off all;  I was not able to control the LEDs while testing.The reason was that the utilized FL1903 control IC  is still pretty unknown on the internet and I only found a Chinese datasheet  for it with the compliant timing diagrams.But since this timing is not supported by the  FastLED library, trust me I tried, I pretty much had to stop my testing here and would recommend  everyone who is interested in such a diffused LED strip, to buy them with a more popular control IC.So all in all this kind of LED strip is not really a hidden gem for me because the only  real advantage it comes with is better diffusion and that is something I like to add on my own.OK, moving on to this box filled with weird looking sleeves that are actually  heat shrinkable wire connectors which I got a pack of 300 for around 12€. Now usually when it comes to connecting wires I love to use Wago connectors but  those are quite a bit more expensive in comparison, they are not waterproof,  do not work with lots of wire sizes and I somehow also think that they  feature a higher contact resistance than the heat shrinkable thingies. So I of course had to try them which I did with 3 different wire sizes by  simply following these 3 shown steps here.And for the most part everything went pretty  smoothly even though the twisting part was a bit hard to do with thin wires. But as you can see the solder connection formed in all cases successfully because that is what we  are basically doing here, using a heat gun to melt solder and thus fuse two wires together. And it also seems like all connections were waterproof. And after doing the electrical resistance test with one of them and a Wago one in comparison,  it was also clear that it features a slightly lower resistance, meaning it  can be used for higher current applications.So It almost seems like the ideal connector  that can also withstand my brute force.But let me tell you that you can not join more  than two wires together, stiff conductors are out of the question because that does not hold up and  it also takes a while to use this connector, while Wago ones can do all of that and are quick to use. But all in all in would still highly recommend them, especially for vehicle repairs or similar.Next I got myself this small 5V fan for around 12€. And I know; such a product does not really sound exciting at first because it can  basically only cool off components or similar.But by simply flipping it around, it can also  be used as a fume extractor whose size is a lot smaller than other commercial solutions out there. The only thing missing was a proper filter for which I got myself a sheet of activated coal that  I cut to size and secured into place.And yes, while I think this solution  is definitely not perfect, it is well worth it for its low price. And since this gadget does not draw much current,  it is pretty well made out of acrylic glass and aluminium and the utilized  boost converter does its job acceptably well, I would kind of recommend it I think.OK, moving on to 3 products at once who basically all do the same thing, but before I get to that;  let me tell you that they were all rather cheap, the most expensive one was 10€. And I got them because I was a bit frustrated by my Jokari whose job it is to remove the  outer insulation from my electrical wires.Now don't get me wrong; the Jokari works  perfectly fine with standard house cable sizes, but as soon as something gets bigger or smaller,  it suddenly becomes pretty useless.And that is why I wanted to try  these three out which according to their product description should be able to do this job as well. I quickly noticed though that the small yellow one was an absolute bad purchase  because it only works with thinner data cables and its quality is not great. The grey one on the other hand works with thicker wires as well but here I got the  problem that changing between cable sizes takes way way too long for me. And that brings me to the red one which might look a bit cheaply made, but it works wonderfully. Simply select the hole where your wire barely fits though, push down and pull. Super simple and after doing quite a bit of testing I can also confirm that  the inner insulation of the cable never got damaged which is really important. So all in all I initially did not expect that, but after testing I would actually  recommend the red wire striper tool, while the other one not so much.Moving on though, next I got myself these two PCBs with  integrated battery holder that you can get for around 4€, super cheap. They are in fact a UPS aka a Uninterruptible Power Supply. And at first sight they seem to do their job perfectly fine meaning after inserting 18650  Lithium-Ion cells, we can charge them up with 1A of current through the USB C port  and we can use the 5V output of the board to hook up a load like a media player. Now the big selling point of such a UPS is that the load still gets powered through the  batteries even when the input power disconnects which as you can see works perfectly fine. There is pretty much no downtime when this happens which was confirmed by my oscilloscope. Other good aspects of the board are that the batteries get charged correctly, the power  really comes from the USB port when a charger is connected, the output current maximum seems to  be like advertised and there is an undervoltage protection for the batteries which is a bit low  for my taste though.So at first sight  this product seems useful, right?Well, after having a look at its output with  my oscilloscope I was quite shocked to see how much noise the claimed 5V DC output comes with. I mean this is so much that it's more like a function generator and the same problem also  applies for the 12V board I got which by the way both have a 5 star rating on AliExpress. So this boost converter design here comes with some serious problems and I can definitely not  recommend it because a few devices will not be happy with such an output voltage.And with that being said we come to the last product which is this small power supply board  with display that only cost me around 25€.That is super cheap considering it can  output 1200W which none of my other lab bench power supplies can do. So as a first test I hooked up a 24V power supply to its input and played around with  its knob and display a bit to not only find out that I can easily set a current  and voltage limit but also that in this case the max output voltage is only around 23V. That is of course because this thing is a buck  converter meaning it can only step down the input voltage. But nevertheless the voltage output and current limit values seem to be accurate  and even after pushing this thing close to its limit with a current flow of 15A,  it only heated up slightly, nice.I of course also measured some input  and output power values to create this efficiency graph here that tell us for  example that with a 12V output voltage we get an efficiency of above 90%, not bad. So after playing around with this thing quite a bit more I was actually pleasantly  surprised and the only complaint so far was that the input fuse is weirdly positioned. But once again there was a big problem with the output voltage and the occurring noise. As a comparison here is the noise of a proper lab bench power supply, they are worlds apart. So even though this small power supply does offer a lot for its low price, I can not fully  recommend it after seeing its output voltage; but you do you and maybe give it a shot anyway.And with that being said we come to the end of this episode and this time there  were not too many recommendations from me; but I still hope you enjoyed it. By the way some of the suggestions come straight from my Discord  server which by the way you can also join by following the link in the video description. And do not worry if one of your submitted hidden gems didn't get featured yet because there is so  much more to cover in this video series.Until then don't forget to like, share,  subscribe and hit the notification bell.Stay creative and I will see you next time.