RC, photos & tech


ZMR250 v2 Build – Part 10 – MW OSD Artificial Horizon Reverse

The Problem:

The default settings in the MW OSD on my configuration resulted in the artificial horizon on the roll axis being reversed.

The Solution:

Edit two settings in the MW OSD firmware.

In config.h, uncomment "REVERSEAHI" as below;

#define REVERSEAHI                // Reverse pitch / roll direction of AHI - for DJI / Eastern bloc OSD users

In screen.ino, I used these settings;

#if defined REVERSEAHI




ZMR250 Build – Part 1 – Parts List

The purpose of this build log is to document the process of building a ZMR250 quadcopter complete with FPV and telemetry. My experience building a previous ZMR250 has been that simple problems like outdated firmware can cause major headaches and heaps of Google searching / forum reading to find the solution. The plan here is to document each step no-matter how seemingly simple it may seem


ZMR250 V2.1 Mini Quad Frame Kit w/PDB Special Edition -

Mini DC-DC 12V Voltage Step-down Regulator Module



FrSky X4RSB 3/16 Channel Telemetry Receiver

Upgrade NAZE32 SP Racing F3 Flight Control Acro 6 DOF/Deluxe 10 DOF for Multicopter

Eachine 700TVL ET25 5.8G 32CH 25mW 7-24V Super Light Transmitter

MICRO MinimOSD Minim OSD Mini OSD W/ KV Team MOD For Naze32 Flight Controller



New DALprop 2 Pairs 5045BN Bullnose Propellers for Racing

Emax BLHeli Series 12A ESC For Quadcopter RC250 Mini200 QAV250

SunnySky X2204S-16 2300kV Brushless Multirotor Motor

Foxeer XAT600M DC5V-22V 600tvl Sony Super HAD CCD FPV Camera

5.8Ghz Circular-polarized Omni Cloud Spirit Tx Antenna



Orangerx, OpenLRSng, Naze32 – PPM input

The Problem:

I need to activate PPM input to the Naze32 board from the Orangerx UHF running OpenLRSng. PPM input is needed so I can use RC5 pin to control some WS2812 addressable LEDs.


The solution process:

In the Cleanflight configurator, enable RX_PPM. Connect the receiver Port 6 output to the RC input pin 1 of the Naze32 board. The problem is when I do that, and switch on the transmitter (ie the PPM stream is presented to the Naze32 input), the Naze 32 seems to lag horribly. Connecting it to the configurator takes ages for the screen to refresh.

I found disabling Telemetry in the openLRSng options for the orangerx Tx module seemed to fix the problem of the Naze32 board lagging. Now I can use the RC5 pin on the Naze32 board to control the addressable LEDs (WS2812).

The only remaining issue is that appears after arming once, then disarming, I can't re-arm with completely removing power from the Naze32.



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