• 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.

    Read more...
  • 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.

    Read more...
  • TVS - Transil diodes to the rescue

    We like to think that voltage in electronics is, if not constant, then at least it’s not going above the supply voltage. So if we apply 5V at the input of the electronic device, it will never go unintentionally above 5V inside.

    It is, however, not true. As soon as you add any type of inductive load (choke, coil, electric motor) things go wild. Current flowing through the inductive element does not like to be interrupted. If it does, it will produce a voltage spike that will propagate to the rest of the electronics. The voltage spike can be high enough to destroy sensitive electronics.

    TVS - Transil diode

    TVS - Transil diode

    Read more...
  • Matek F765-WSE flight controller preview

    Who makes the best fixed-wing flight controllers? Most probably Matek. Their series that begun with Matek F405-WING in 2018 is still going strong. Some models are end-of-line and new ones are created. The Matek F765-WSE is the next generation of Matek WING flight controllers that will appear on the market in late Q3, early Q4 of 2021.

    Matek F765-WSE flight controller

    Read more...
  • 7-inch Source One long-range drone flies again

    My 7-inch TBS Source One was my first 7-inch drone that flew great. For quite some time it was my favorite and the most advanced FPV drone. However, then I designed and started using Pirx Seven, Source One landed in a closet. The fact that it was not DJI HD FPV system compatible only made me fly it less and less over time.

    Last week it changed. It turned out, I need an “analog FPV” drone to run some tests of the Sentinel AAT antenna tracker and perform INAV experiments. It turned out, this was my very last quad that still had an analog camera and VTX installed. As a result, 7-inch Source One is back from the grave, and even got some updates!

    7-inch TBS Source One

    Read more...
  • How to replace the 3d printer nozzle - Prusa i3 MK3S

    The Prusa i3 nozzle is of good quality. If you treat it well, it will serve you for years. My Prusa i3 MK3S was printing without absolutely any problems for more than two years. Unfortunately, some of the failed filament experiments left too much fowling in the nozzle and although it was printing fine most of the time, at one point I said enough and bought a new one.

    If you want to know which one, I got steel, nickel-plated E3D V6. The one that came with the printer was brass.

    The process of replacing the nozzle on your Prusa i3 MK3S (and similar) is quite simple, but you will need a few tools:

    • 2.5mm HEX screwdriver or Allen wrench to remove 4 screws
    • 7mm flat wrench
    • Adjustable wrench “Swede” type or something similar

    Step 1

    Prusa i3 MK3S nozzle replacement

    Read more...
  • How to protect ESP32 OLED display from cracking

    As great as some ESP32 development boards are, they are very far from perfect and many different models can have different problems. Like, for example, ESP32 with an OLED display. If you do not handle those boards very carefully, you will destroy them in no time. The OLED screen is not protected and edges are very prone to damage. Even a not-so-strong hit on the OLED edge can crack them.

    ESP32 OLED displays cracks here

    Read more...
  • ImmersionRC Ghost GPS Telemetry

    ImmersionRC Ghost 2.4GHz long-range LoRa based radio system was announced a year ago and is available on the market for only a little shorter. In this time, ImmersionRC put quite an of effort into making it better, but for unknown reasons always ignored one very important aspect of a long-range radio control link: telemetry!

    OpenTX with IRC Ghost Telemetry

    Read more...
  • How to use stepper motors with Arduino

    Stepper motors are the workhorse of modern automation and mechatronics. You want something to more and move precisely how much wanted it to move? You use a stepper motor. This is why, we use steppers in cars, robots, all kinds of automation, 3D printers, CNC machines. You name it.

    Stepper motors

    The main difference between a stepper motor and any other electric motor is that the stepper, when electricity moves through its coils, will rotate the shaft only by a defined angle, one step. If you want it to move another “step”, you have to energize the coils in a different way. The step is constant for the motor. For example, a motor with 100 steps per resolution, will always move 3.6 degrees per one full step. Motor with 200 steps per revolution will move 1.8 degrees per step and so on.

    Read more...
  • Artificial intelligence for developers - GitHub Copilot

    Artificial Intelligence, aka Skynet, is very often overhyped by companies and underhyped by developers (there is no AI, it’s just another IF in the code). It does not change the fact, that AI is used in more and more places. Just look at Tesla autonomous pilot. And for years you can hear that very soon this or that job will be replaced by artificial intelligence. Is that true? No, I don’t think so. Still, who knows how the future looks like?

    What would happen if you feed trillions of lines of code hosted publicly on GitHub to AI? Would you create an Artificial Software Developer? No, but maybe a useful tool would be created? A tool that suggests you not only single lines of code but whole functions and code snippets? Even based on comments? Why not!

    Artificial Intelligence for Developers - GitHub Copilot

    Read more...
Paweł Spychalski

If you have any comments or questions, or just want to say "Hi, Pawel, good job!" you can always drop me a tweet!