• LILYGO T5 4.7-inch E-paper ESP32 development board

    One of the biggest advantages of ESP32 development boards (without even counting the speed, flash size, WiFi, Bluetooth, and two cores) is that they come in a variety of shapes and sizes: bare boards, with OLED, with color LCD, with LoRa chipset, with GPS modem, etc., etc. And finally, you can get them with an e-paper display.

    LILYGO T5 4.7-inch E-paper ESP32 development board

  • The State of the RC/FPV Hobby Q1 2021 - The results

    A few months ago I aske the RC/FPV community a series of questions what they use and how they fly. Today, it is time to announce the results!
    In total, I got answers from 1739 people. I will not lie: the number is like 10 times higher I expected it to be. So that you! I appreciate the effort!

    Let's go through the question one by one, with a short commentary.

    In the last 3 months I've been flying...

    In the last 3 months I've been flying...


  • Pirx Seven vs DJI FPV

    Pirx Seven 7-inch FPV frame

    I designed the Pirx Seven 7-inch FPV frame when the DJI Digital FPV System was something as a novelty. Truth to be told, back then I have not believed it will so popular as it is today. Turned out, I was wrong on that and the DJI Digital FPV System is incredibly popular. Luckily, the Pirx Seven turned out to be future-proof and it accepts both DJI Airt Unit and Caddx Vista without much effort.

  • How to generate PPM signal with ESP32 and Arduino

    The PPM protocol for encoding Remote Control channel values is now a legacy. Still, it is widely accepted by different hardware and when tinkering with Arduino, remote control, and working on own accessories for flight controllers, PPM is still a valid option.

    A few years ago I presented a code that allows generating PPM stream using Arduino and AVR hardware. That solution is very hardware-specific and works only with ATMega microcontrollers.

    During my work of ESP32 DiyMotionController I stumbled on a problem: if ESP32 is not compatible with AVR when timers are a concern, how to generate a PPM stream on ESP32?

    PPM signal on an oscilloscope

  • ESP32, Arduino and Timer/Alerts

    Because of completely different architecture, ISR and Timer solutions known from other Arduino compatible platforms, especially AVR/ATmega does not work on ESP32. They don't. At all. If you would like to port any code that uses timers from AVR Arduino to ESP32 Arduino, you would have to rewrite them completely.

    However, timers and alarms with espressif ESP32 Arduino core are simple. Much simpler than AVR equivalents! No more writing registers with magical numbers.

  • DIY Drone Gesture Control - DIY Motion Controller

    Together with the DJI FPV Drone we, RC and FPV hobby enthusiasts, got a new accessory: DJI Motion Controller.

    DJI Motion Controller

    It does a pretty obvious thing that we know for years from the Nintendo Wii controller: with this device, you get gesture control over your FPV Drone. You tilt it left, drone turns left. You tilt it back, drone gains altitude. You press the index finger "trigger" and the drone goes forward! There are some problems though. First of all, it works only with the DJI FPV Drone. And second of all, it cost an extra $200!

  • ESP32 and multiple I2C buses

    One of the advantages of the ESP32 microcontrollers over the competitions is dual-core architecture and two I2C buses.

    Yes, the I2C bus allows connecting multiple slave devices to single pair of SCL SDA wires. As long as slave device addresses are unique, everything will work just fine: OLED display, LM75 temperature sensor, MPU6050 gyroscope. However, one has to remember that one of the devices can be polled at a time. If the bus is used by, for example, MPU6050, parallel communication with SSD1306 OLED display is not possible.

    Here comes the advantage of having multiple I2C buses. Not only you can have more devices of the same type and avoid I2C address conflicts, but you can also take full advantage of 2 ESP32 cores and communicate with multiple devices at the same time.

    ESP32 with OLED

  • FPV meets corporation - DJI FPV Goggles V2 vs V1 and availability

    Why can't I buy DJI goggles anymore

    All of you who tried to buy FPV goggles in the last three months might have noticed that it was not a trivial endeavor. Starting from the last December, the DJI Goggles and Air Units and Caddx Vistas availability was limited. To some extent, it was due to increased demand just before Christmas and so some, because V1 goggles production ended a few months ago and what we were getting on the market were units produced probably in the Q2-Q3 of 2020.

    DJI FPV goggles


  • QmuBeacon - ESP32 and LoRa based GPS recovery beacon and locator

    Having a broken leg, limited mobility, and paid sick leave have some perks after all. I've finally found some free time to sit on the project I started, I think, two years ago: ESP32, LoRa based GPS beacon, and locator. You know, put it on an airplane and have a way to get the distance and bearing when you crash.

    ESP32 LoRa GPS beacon and locator

    In the last few days, I finally managed to:

    • Improve RF handling and make it more robust as well as send more data from the beacon
    • The Locator can work as a beacon too
    • Multi-beacon support - single Locator can track multiple beacons at once
    • Some other fixes and improvements

    The future is also bright since, if time allows, I intend to integrate it with INAV as well. But now, it will not act the same way as INAV Radar. I have different ideas for that. That might be interesting, right?

    If anybody would like to talk about the project, here is the Discord channel for that https://discord.gg/q9vC66R9bA

  • Diatone Roma F4 LR: Long-Range on 4 inches

    For years, long-range drones were associated with big and purpose build (mainly lightweight) quadcopters. With at least 7-inch propellers, but true long-range started at 8-inches or more. Times changed, and in the 2020, a new class of long-range FPV quadcopters emerged: light, dead-cat frame, 4-inch propellers, weight around 250g, and with flight times somewhere between regular cruisers and purpose build long-range machines. Sure, they are not capable of going as far as "true long-range," but far enough that majority of pilots consider them build for distance.

    Diatone Roma F4 LR Long-range drone

    The Flywoo Explorer LR 4 is considered as a protoplast of the class. Competion does not sleep and today let's take a look at the Diatone Roma F4 LR


PaweĊ‚ Spychalski

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