A clip of the same few seconds, but taken from the in-goggles recording with the OSD data overlaid. This is what I saw while I was flying.

To sort out the antenna mounting I literally dusted off my 3D printer and made some shims/bushes to go around the bottom of the antenna tubes. They're a good, snug fit in the antenna mount now, though I may still need to add some glue to make them crash-proof.

The gel tape holding the GPS receiver to the battery strap is not going to last very long, but it's just a temporary fix while I find out whether the relocation has fixed the interference issue. If so I'll come up with a more permanent solution, probably involving a needle and thread.

Anyway, ready for some more testing I think. I'm really hoping to get both GPS telemetry logging and GPS rescue working reliably before my trip to Paranal Observatory.

This evening it was time to repair the GPS module's wiring, and see if I can do anything to reduce interference.

Previously I had the GPS wires running in between the flight controller and video transmitter, past the cables for both the video transmitter and camera, to the GPS receiver's location directly above the camera. This time I decide to route the GPS wiring upwards from the flight controller, away from the video transmitter, camera, and their cables, with the idea of mounting the GPS receiver on top of the battery strap. Since the GPS wiring would now be very exposed I put on some heat shrink and electrical tape to protect it a bit.

I took Eric the half-a-quad outside and using my phone, a USB-OTG adaptor and the mobile version of Betaflight configurator I was able to power up the flight controller and GPS receiver and test it. This time it got up to 13 satellites, as it should! This confirms that the GPS receiver is working, and that the previous problem was probably due to interference, but it doesn't confirm that I've fixed the interference.

During this test the video transmitter and camera weren't even present, and the motors and ESC weren't powered. I won't know whether I've really fixed the problem until I do a test with the fully reassembled, fully powered up quad.

So... mixed results from the flights on Sunday.

The GPS receiver was functioning, but at no point was it able to get a lock with more than 6 satellites. That's not good enough for GPS rescue, and a lot less than an M10 receiver ought to get in the open air. My assumption was interference: it's a very small quadcopter packed with unshielded electronics and cables, and two separate 2-way radio systems.

The new VTX antennas seemed to be working fine, but it was quickly apparently I'd need something better than a blob of hot glue to hold them in place properly.

I did a bit of casual flying around until I had a violent encounter with my old nemesis, the soccer goal crossbar. It was a glancing blow to the forwards upper left of the quad, dislodging the GPS module from on top of camera, slightly denting the battery, and doing some minor damage to the carbon fibre at the front left motor mount. The front left propeller also acquired some career ending nicks, and the GPS module wiring was damaged, possible due to contact with the front left propeller.

On that topic, Caddx need to raise their game. There was not a single sticker included with the GoFilm 20 I bought recently. Not with Caddx branding, nor with Walksnail.

Meanwhile even the batteries that I bought to go with it each came with a small sheet of stickers!