This is a sub 250g digital freestyle or longrange prototype drone. It's equipped with a caddix vista (nebula) digital FPV system (cam, VTX, antenna combo), TBS crossfire diverstiy receiver and GPS.
For an analog of this frame, check out https://rotorbuilds.com/build/25089.

Hints

The UART6 on the BetaFPV Toothpick F4 V3 is not a "real" uart, it's only soft serial. Therefore it is not recommended to use the "fake" UART6 it for the RC link. You need to have Soft Serial activated (in betaflight), in order to be able to use the soldering pads labeled with TX6/RX6. Additionally, the default resource mapping for soft serial RX11 is set wrong. You need to change the PIN to B10 in the CLI.
resource SERIAL_RX 11 B10

If you flipped the AIO (upside down flip, 0°) like me, which allows is to be closest to the top plate (because, that's used to be on "normal" frames), you also need to remap the motor resources in the CLI to this (just switch motor 13 and 24)
resource MOTOR 1 B06
resource MOTOR 2 B07
resource MOTOR 3 B04
resource MOTOR 4 B05

If you do want to use RPM filtering (which is nice, but not really mandatory as this build is quite clean), make sure to only go for 4k PID Loop and Dshot 300 and have overclocking activated (108mhz is default for this board). You will have to flash the ESC firmware, as the ESC is only BLHeli_S and does not support bidir dshot out of the box. In order to use RPM filters, it is required flash it to an "inofficial" version (Jazzmaverick Edition). Currently Version 16.73 (G_H_25_REV16_73.HEX) is recommended, but 16.9 available at the time. I tested both, and both worked fine. Except, that the poor F411 is quit at it's limits with RPM filtering on (Betaflight 4.2.3).

For the maiden flight the master slider is set to 0,8. Everything else is pretty much betaflight defaults. Later, I tuned it to be a little more "cinematic" and less agressive, more D, lower FF, lower I-term relax. With RPM filters are on, the filters can be reduced in strength for this setup.

I also flipped the caddix airunit (upside down flip, 180°) in order to have the antenna at maximum length. This has some downside effects, but the antenna was most important to me. One of the downsides is, the AIO would touch the airunit this way. To mitigate that, the airunit is mounted with 3mm M2 spacers inbetween AU and plate. To now fit the AU, the upper front 3D printed part (rail holder) had to be mounted under the main plate, instead of on top. That's why pate and rails are not in parallel. Well, I like it that way, but it's not mounted as originally designed. I also just could get a longer antenna. Because another downside is the relatively long power and signal cable, as it has to go all the way to the other end of the AU. I used AWG26 calbes for VBAT and GND to compensate, but I am pretty sure, it does not matter at all.

Take care the motors are with 9mm hole distance, as other 1404 have 12mm.

Parts

• Xplora Frame (Prototype)
• Caddx Vista (Nebula)
• 1404 Motor with 9mm hole distance (GEPRC MOTOR 1404 3850KV)
• BetaFPV Toothpick F4 2-4S AIO FC 20A V3
• TBS CROSSFIRE DIVERSITY NANO RX (antennas included)
• 3 Blade Props (BETAFPV Gemfan 16pcs 3016 3-Blade Props with 1.5mm Shaft)
• M2 screws 20mm, 3mm, 6mm
• M2 standoffs 20mm
• 3D printed parts (TPU)
• Beitian BN-180 GPS

Flight time is at least 8min with 4S 650mA.

Link to some flights: