How BAD are cheap 18650 Li-Ion batteries from China?

China is a magical place where you can get everything for a fraction of a price. Like 10000mAh 18650 LiIon batteries for $1.5. Of course, we have to begin with a note, that there are no 10000mAh 18650 batteries! Technology does not allow for such energy density. And if they would exist, they would not cost $1.5. Closer to $15. Anyhow, I’ve bought a couple of cheap 18650 on Aliexpress and tested them with a DIY OpenSource OpenHardware Arduino-based battery discharger.

Colorfabb LW-PLA Light Filament

There are many 3D printing filaments to choose from. Each of them has its own specific features: PLA is simple and easy to use, PET-G has more temperature resistance, Polypropylene can be bent and TPU is indestructible.

If you look for a filament that gives the lightest prints, there is only one option: foamed PLA filaments called LW-PLA. Today let’s take a look at the LightWeight PLA (LW-PLA) from Colorfabb.

BlHeli Motor Timing Explained

What is motor timing? You can change it in the BlHeli configurator, but what does it do? Many tutorials say that you should increase Motor Timing. What is the gain of doing so? And why is it in degrees (at least in BLHeli_32)? The short answer is: higher timing equals slightly more torque but less efficiency.

Can you sell Open-Source software?

Many companies are afraid of Open-Source software. There are myths and misunderstandings. One of them is: can I sell open source (GPL, MIT, Apache License) to my clients? The answer is both yes and no.

There is nothing that prohibits issuing an invoice for Open-Source software. However, license transfer can be tricky. You will learn more in the video below.

GoPro Media Mod microphone quality

GoPro makes great action cameras. Small, tough, with image stabilization and other cool features. For some time now, they can be used also for more “professional”, cinematic purposes. I’m recording quite a lot of my videos with the help of GoPro Hero camera. Previously with Hero 7 and Hero 8. Now with the Hero 10.

The problem with the latest Hero cameras is that they do not have the HDMI out or microphone port. To have them, you have to buy the Media Mod.

GoPro Media Mod has its own microphone that is supposed to be better than the one built-in into the camera itself. But is it?

GoPro Hero 10 Black

GoPro releases the new action camera every year. Usually around September. This year was no different and only a few weeks ago we’ve been presented the anniversary release: GoPro Hero 10 Black.

I purchased my Hero 10 a few days after the premiere. My target usage for this GoPro was: I need a smaller camera to record videos on the outside for my YouTube channels and maybe a better one to put on my FPV drones. One week later I know everything. For the first of those purposes Hero 10 is dope! For the second one, not so much.

FS1000A and XY-MK-5V - How they work - cheap 433MHz Arduino radio

The FS1000A transmitter and XY-MK-5V 433Mhz receivers are probably the cheapest options if you want to do any kind of radio transmission with Arduino. And many people assume that it will work in their application no problem.

The truth is, that it’s not that simple. The way how whose 433MHz radio modules are made puts multiple limitations: They do not add any encoding or packeting. It’s just a pure radio layer. Your Arduino code has to do the coding and decoding of the incoming signal. You can not transfer data too slowly, as the receiver will boost sensitivity and start outputting random noise on its output You can not transfer data too fast, as the signal will be lost

If you are interested, you can listed about all the details in this video

My YouTube streaming setup

Becoming a YouTuber was one of the most surprising things that happened to me. One day, while laying in my bed, I thought that if some other guys can do it, why can’t I? I know things, I’m not afraid to talk, so maybe it’s something I can do as well. And just like that, started to record my first videos for YouTube. When I look at them from the perspective of the time, oh boy, I sucked so much at it! Audio, video, my behavior, the way I speak, it all sucked!

Five years later I still suck, but that’s fine. I suck slightly less and apparently that’s just enough. Over the years of experiments, I gathered video and audio equipment that satisfies my requirements. It’s maybe not perfect, but it was reasonably cheap.

Gearbest bankrupted

Being an electronics retailer from China is not an easy piece of bread. Competition is fierce and current electronic prices are very high. On top of that, European Union VAT rules became much more strict. Every package that enters the EU has to have VAT collected from the recipient. As a result, fewer people are buying in China.

As a result, the first recognizable retailers filed for bankruptcy. GearBest website is down, you can not view, order or check your parcel.

Is 6S more efficient than 4S?

There is a popular opinion, a myth maybe, that drones powered by 6S LiPo batteries fly much longer and are much more efficient than their 4S counterparts. You know, lower current and lower KV motors need less current for the same torque.

The problem with this opinion is that it’s only partially correct. Yes, the higher voltage will have a lower voltage drop and the current is smaller, but the real-life difference is so small, that it adds nothing to the practical “efficiency”.

To compare 6S and 4S drones everything has to be equalized. KV of the motor scaled correctly, battery size and C-rating adjusted as well. And on top of that, it’s not voltage or current that flies the drone. It’s power. And like all energy, power has to be conserved. The lower current means higher voltage. Lower KV higher resistance and so on.