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!

The basic layout remainded as it was. It’s still running with INAV, still has:

• Matek F722SE flight controller
• Avenger V2 2507 1500KV motors
• Tekko32 ESC
• Beitian BN-880 GPS

One might say: classics, nothing changed from the previous iteration of this drone. And that’s true. Basic parts remained the same, as they are well proven to be working just fine! The most important changes are in the back of the drone.

First of all, I got rid of the FrSky R9 radio link. It was great in 2019, but things have moved on and in 2021 we have amazing long-range 2.4GHz radio systems now. This is why, Source One, like most of my flying and driving contraptions, was upgraded to use ImmersionRC Ghost. Why? Ghost and not TBS Crossfire? Shorter antennas, more than enough of a range for my needs. And slightly cheaper too.

Second of all, this FPV drone has an experimental (still) BNO055 secondary inertial measurement unit. I wrote more about it in 2019. Long story short: the secondary IMU (Inertial Measurement Unit) in form of a small, external sensor in a for on a Bosch BNO055 can improve the navigation performance of INAV. After all, it has its gyro, accelerometer and magnetometer sensor fusion that is proven to be working. The gyro itself is rather crappy, but 3 sensors combined do give nice full rotation vector data. Both in Euler angles and quaternions. More experiments will follow.