I don't know about this Finding Hidden Gems on AliExpress is truly satisfying; I mean that is why I have been doing this video series for 9 episodes now. And in case you are completely confused, then let me tell you that AliExpress is a Chinese Online store where you can find the newest, weirdest and also sometimes super useful products. But then again there is also lots of garbage on this site which is why in this video series I test interesting looking products, to ultimately tell you whether you should check them out or simply ignore them. And in today's special 10th episode, I will have a look at the products that did not quite fit into the previous videos meaning I not only get to decluter my AliExpress Drawer, but you also get an extra full episode featuring 8 different products. Let's get started! This video is sponsored by Ground News, more about them later. Now let's kick things off with this electric hand drill grinder that you can get for 2€, pretty cheap. In episode 3 of this show I actually made fun of this thing, but then viewers came forward saying that it is actually useful, so I had to test it. Now this product supposedly comes in handy when your drill bits are getting dull or damaged which definitely happened to me before. So by attaching a drill to the gadget, pushing the drill bit in there and then giving it all a go, it supposedly sharpens it. And before having a look at the result under the microscope, let me firstly say that using this thing was pretty easy and intuitive to do, drill bits from 2mm up to 12.5mm fit in here and you can easily change the grinding wheel within 1 minute, nice. And to my own surprise I think this thing actually worked and made the drill bit sharper which I didn't expect because the product page says that it is not suitable for hardened drill bits. So yeah pretty useful tool I would say which of course does not work for all my drill bits; but I would still recommend giving it a shot. Next we got this USB Data Cable Tester here that you can get for almost 1€, super cheap. To use it, you have to firstly supply 5V power and afterwards you can connect your to be tested USB cable between the upper and lower side of the board. Then some LEDs in the middle light up, basically telling you what pins of your USB cable have an uninterrupted connection between both sides. This is of course useful to test whether your cables are broken. And if you had a problem like me before, that you were using a USB cable and wondering why the data connection didn't work, then you can also use this board to easily find out whether your cable even has data wires. For these two purposes definitely a handy board to have around; but sadly it does not give you additional information for USB-C cables like what power rating they support and for me Mini USB is also missing here. But even with these slight problems; I would still recommend this board. Moving on to the third product which are these magnetic Pogo pin connectors that you can get for around 1.2€. I got interested in them because joining two PCBs together is not best done via solder connections. I mean you can of course use other connector types, but these just seemed elegant. And at first sight, the quality is very good, the magnetic pull is pretty strong, you can not reverse the polarity because of the magnets and you get the exact mechanical dimensions of all connectors, very nice. And of course this solution works just fine for low power circuits. But I was wondering how much current this connector can handle. To find that out I simply let more and more current flow through it while measuring the voltage drop across it which gave me an average resistance of 10mohm. That is 5 times higher than the resistance of my Wago connector here meaning we should probably use it for 5 times less current which is still pretty good though. So all in all very happy with these connectors which is why I would definitely recommend them. And If you are like me and love technology news, let me quickly tell you about Ground News. Now I rarely have non electronics sponsors on this show and I am making an exception here because I really like what they’re doing. Their app and website developed by a former NASA engineer gathers all the worlds news in one place, let’s check it out. This week for example, scientists designed a space suit that can convert excrement into drinking water! And I can access more than 20 articles published on it world wide. Some sources claim it was inspired by Sci-fi movie Dune while others like the Sun out of the UK focus on the benefits of letting astronauts roam longer. I’ve been following news on things like Tech and Solar Power to stay up to date on the industry and even see what the media might not be covering with their ‘blind spot feature’ If you also want to stay fully informed, go to ground dot news slash greatscott or scan this QR code and subscribe through my link for 40% off unlimited access. With that being said let's move on to the next product which is this BM6 Battery Monitor here that you can get for around 23€. Such a product mainly gets used for a car battery and I can definitely can get behind that because my battery broke twice inside my old car here and not being able to drive during the cold morning hours during winter definitely sucks. So being able to monitor your battery voltage and getting notified about abnormal behaviour sounds like a really good idea. To test this, I simply attached the circuit on top of my battery, hooked it up not optimal to the plus and minus pole, installed the required App, paired and connected everything and then went for a test ride. After coming home, I checked the app and was happy to see that it tracked everything like voltage and temperature and also let me know that cranking worked just fine as well as charging the battery, lovely. So at first sight I was super happy with this thing and simulating abnormal behaviour with my power supply also triggered the alarm. Combine that with the fact that its current demand will only drain your battery completely in a couple of years when not getting charged at all, the reverse voltage protection works and the overall quality of the PCB is pretty good and I got to say that I was very pleased. Probably the only negative aspect is that the app gathers GPS data from you to for example let you know where you parked your car which seems harmless at first, but then you read a review like this and start to get a bit worried. But don't sweat it because you can turn off GPS in the app meaning I can fully recommend this product. Next let's have a look at this TES200 Logic IC tester that you can get for around 25€. I got interested in it because I have a box full of 74 and 40 series logic ICs. These can basically fulfil a whole bunch of different functions and I think nowadays they are still useful for many different circuits. But of course it sucks when one of these ICs doesn't work and you waste hours trying to find the problem, not realizing that the IC was broken to begin with. And that is where this tester can supposedly help. After powering it with 12V, I firstly had a closer look at the user interface which was very intuitive to use. I mean you simply choose the IC number, click test and it does its thing. And after finding out how to correctly insert ICs, I did just that and pretty quickly found out that it works like advertised. The only real downside of this thing is that not all 74 and 40 logic ICs are in its database. But besides that definitely a useful tool if you are working regularly with logic ICs. Next we come to the sixth product which is this Tang Nano 9K FPGA that I got in combination with a small display for around 19€ in total. That is certainly a rather low price when it comes to FPGA boards and in case you are wondering; FPGAs are different than Microcontrollers because with those you basically configure tons of logic blocks inside the IC. That is why they are way faster and also different to program. But you can easily see that they mean business because of the included HDMI connector. So after installing the given IDE for this FPGA, I followed a well written tutorial given by the manufacturer in order to light up some LEDs which worked out just fine. And it seems like there are quite a lot of resources available online to learn programming for this thing. But since my review time is limited here, I was happy to see that there was an example code for the display and HDMI connector available which both also worked perfectly fine. And when we consider that there already exist a few projects around this board, I feel like this could be a really fine board for FPGA beginners like me. Moving on to this round digital tape measure though that you can get for around 17€. Initially I got intrigued by it because the idea of rolling this thing over a surface to measure stuff seemed rather odd. And first off the positive aspects; like that this thing works pretty accurate with a resolution of 0.1cm, charging works just fine as well as all buttons and modes. But measuring a straight line with this thing just seems more time consuming and cumbersome than simply using a laser tape measure. I can only really see its use when it comes to rounded surfaces which I honestly never wanted to measure. Besides that, it also kind of sucks that the manual is only in Chinese and the user interface with all of its modes is not really intuitive to use which makes the manual mandatory. So for me it is definitely a mixed bag and since I don't see the point of using it, I have to give it a thumbs down. And that brings us to the last product which looks like an ordinary battery holder at first sight, but it actually comes with a protection PCB on its side and you can get this thing for around 13€. After loading it up with 4 18650 Lithium Ion cells and giving it a short charge pulse, we basically got a 12V battery pack that we can use for projects. This is definitely a quicker solution than welding cells together and then adding a protection circuit. But does it work just as good? Well, to find that out I had a look at the given protection features and wrote down the most important ones to test. To do that, I firstly replaced one cell with super capacitors to find out whether overcharge protection as well as over discharge protection works, which they both did. Then I tested the overcurrent protection which kicked in at 6A, lovely. So you might be thinking that everything is perfect. But what you definitely have to keep in mind is that this protection circuit does not balance charge the individual cells meaning that overtime their voltage can drift apart and thus you can not fully charge up the pack before the overvoltage protection kicks in. To solve this problem though you got these pins here which are connected to each cell meaning you can solder on a balance connector and use a suitable charger to properly charge up the battery pack. Besides that it is also worth mentioning that the battery holder creates kind of a big voltage drop when drawing above 3A. But to power low power projects, I would certainly recommend this thing. And that bring us to the end of this special 10th episode and I am happy to say that most products were truly useful. As always I hoped you enjoyed this video and you are looking forward to more hidden gem videos as well as my usual electronics videos. To not miss them don't forget to subscribe and hit the notification bell. Stay creative and I will see you next time.