Troubleshoothing INAV: magnetometer/compass is not working

Your magnetometer/compass is not working with INAV? Is the sensor red in Configurator? You are not the only one… Not only most popular compass HMC5883l is discontinued and what you get are Chinese clones, chip labeled 5883 might not be HMC5883l but something completely different. And I2C bus is very very picky and likes to give up on you….

This is how you might fix your problems: add pullup resistors for I2C SCL and SDA lines and/or lower i2c_speed

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Troubleshooting INAV: why INAV is not arming

Few weeks ago I've decided to shoot more tutorial videos about INAV and this is the first effect of that decission: INAV Troubleshooting: why INAV is not arming

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How to wind an electric brushless outrunner motor with dLRK winding schema, part 2

My memory is not as good as it used to be. I just realized, that third part of my motor winding series was not yet announced over here. So here we go…

In this video I terminate motor into Delta pattern and do first test of freshly winded motor.

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Standalone Betaflight Configurator, since Chrome Web Store apps are dead

Google finally did what they announced last year: Chrome Packaged Apps for Windows, Mac, and Linux are dead. OK, maybe not 100% dead, but they were removed from search and browse in Chrome Web Store. If you still have link, you can install (no idea for how long tho).

So, how to live with that? Our hobby is driven by Chrome Packaged Apps. Betaflight Configurator, INAV Configurator and Cleanflight Configurator are all Chrome Packaged Apps. Did we lose the ability to set up our drones? Luckily no. Thanks to fantastic project NW.js, chrome apps can be packed together with Chromium and distributed as a single file without dependencies. I've prepared a short video how to install Standalone Betaflight Configurator, for INAV it's the same procedure. And for Cleanflight… well… Cleanflight is dead. Or rather dying…

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How to wind an electric brushless outrunner motor with dLRK winding schema

This time, another "motor winding" video. In 13 minutes and something seconds I:

  • show some tool that I find useful for motor winding
  • wind a 12N14P brushless outrunner electric motor with dLRK winding schema
  • terminate this motor into Delta configuration

BTW, in next video I will show you if it worked or not 🙂

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Video tutorial: 5.8GHz Inverted Vee antenna for FPV

Today another video tutorial. It's just simpler to show how to make something on video than with text and images. So, without further ado: How to make Inverted Vee antenna for 5.8GHz FPV at home. All that is required is:

  • coax cable (here RG316)
  • SMA/RP-SMA connector
  • copper welding wire
  • caliper
  • soldering station
  • basic tools

At the end we have small and light FPV antenna that just works. Sometimes it's just worth to make something by yourself, right?

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Betaflight 3.2 Dynamic Filtering Explained

With upcoming Betaflight 3.2, we will be given a new, outstanding, new feature: dynamic filtering. An belive me, it was worth waiting for Betaflight 3.2 only to get it. I do not care much about other changes that happened with version 3.2 but dynamic filtering it the thing! In this post I will explain, in simple words, what is dynamic filtering and how to enable it.

The problem of noise

Gyro has a nasty tendency to pick up a lot of noise. Vibrations. After all, there are a lot of things that can vibrate (motors, propellers) and resonate (frame). Without a good way to filter all that noise out, our racers would not fly as good as they fly now. And you would be replacing motors and ESCs even more often. I you want to know more about gyro noise sources and filtering, please watch my Gyroscope and filtering series on YouTube.


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Understanding Dterm: how Dterm really works

I will be very honest: until very recently I did not really understood how PID controller’s Dterm really works. Yes, something with dampening, something with “looking into future”, bla bla bla. But the reason for not understanding was because I was overthinking it. There is no “magic” only simple mathematics and few basic concepts which I will now explain.


Setpoint is the value which we request from our system. In case of multirotors, PID setpoint will be a rotation speed around axis given in degrees per second [dps]. Setpoint 0 means we do not want to rotate (keep current attitude) and setpoint 200 means we want to rotate at 200dps


Measurement the value that represents actual state of the system measured by some kind of sensor. In our case, it will be the gyroscope and rotation-around-axis speed measured in degrees per second


Error the difference between Setpoint and Measurement computed as Error = SetpointMeasurement. In our case, when Error is above 0, that means drone is rotating too slow and should speed up. If Error is below 0, drone is rotating too fast and should slow down

Understanding Dterm - setpoint measurement and error (more…)

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