Diatone 250 build

This is my first real quadcopter build.

It is based on the Diatone 250 frame, some Multistar elite 2204 2300kv motors and the naze32 flight controller.

DSCF3916

The Naze32 rev5 does not work with sbus without an additional inverter so i first tried to just use pwm.

Even without flying i noticed an annoying delay in the throttle response so i tried to use sbus anyways and bypassed the inverter in my x8r.

DSCF3917I will still have to change the flight controller later as i want to use s.port telemetry, which won’t work with the naze32 rev5.

To save a bit weight it should also be a good idea to clean the wiring and switch to the smaller frsky x4r receiver.

Pretty much finished now:DSCF3920Even with stock pids it hovers fine:

RC Remotes with smartpropoplus and rtl-sdr

Some years ago i loved smartpropoplus, a software that lets you use any rc remote with trainer port on you soundcard to emulate a windows gamecontroller.

Data test
Looks like PPM

While playing around with rtl-sdr i found out that my receiver can receive the 35mhz band and tried to capture some ppm data from a 35.11mhz Hitec Optic 6 remote and the results were great:

I decided to direct the fm decoded signal from sdrsharp via VB-Cable into smartpropoplus to check if it can be decoded and it worked.

smpp rtl1
Raspi as rtl-sdr receiver with sdrsharp and smartpropoplus

The next time i used a raspberry pi to receive the signal and direct it via rtl_fm and aplay into a soundcard input the same way the remote would be connected with a trainer cable.

The latency is pretty high because of rtl-sdr but this method works great with any remote control and it is not longer limited by a trainer port and you get some pretty good range.

It makes no difference in the delay if rtl_fm or sdrsharp is used but  rtl_fm is of course better for any „real“ use.