Update 23-Nov-2020: Part 4 video added, and HMI released (see below)


A rotator controller project based on the popular K3NG rotator controller.

This project features;

• Teensy 3.2 microcontroller

• Nextion 3.5″ Enhanced HMI with custom user interface

• GPS serial data pass-through to USB for time-syncing PC

• Yaesu G-800DXA (and G-1000-DXA, G-2800-DXA) azimuth rotator control

• Yaesu G-800DXA (and G-1000-DXA, G-2800-DXA) PWM speed voltage output

• Az analogue potentiometer input

• El analogue potentiometer input

• Yaesu G-5500 compatible for CW/CCW/Up/Down control

• PWM motor driver for linear actuator elevation control

• i2c extender for remote sensors via cat5

• Audible alert output

• Teensy RTC battery connection

• Four NO push-button switch inputs with pull-ups


Main controller during development on breadboard, and Nextion touchscreen. 

Remote unit at the end of a 30m (100ft) run of cat5 cable.


Elevation sensor is an ADXL-345 accelerometer.  i2c extenders at both main and remote unit are P82B96 dual bi-directional bus buffers.

Primary Nextion screen, one of many pages available.

Nextion screen is responsive to features set in Arduino files, so you only see what is relevant.


Nextion HMI features:

• Numeric Azimuth and elevation display

• Gauges Azimuth and elevation display

• CCW/CW/Up/Down rotator control

• Configurable preset positions with names

• Configurable colours/fonts

• Park button

• Go To grid square

• Co-ordinates converter – convert between lat/lon and grid square

• Configuration – Screen

• Configuration – Rotor

• Numeric keypad for entering numbers

• ABC keyboard for entering text & numbers

• Diagnostics page

• Moon & Sun tracking page

• Satellite tracking page

• Satellite selection list

• Satellite AOS page

• Satellite tracking world map


At VK4GHZ, Yaesu G-800DXA rotator for azimuth, and linear actuator (being driven by a MC33926 Motor Driver Carrier board) used for elevation control.



3D Renders – main controller board:



Schematics and PCB Overlays (pdfs)

Main Board (updated 17/10/2020)



PCB Top – K3NG Rotator Controller Main V3


PCB Bottom – K3NG Rotator Controller Main V3



Remote Board (updated 11/9/2020)




Bill of Materials



3.5″ Nextion .tft (updated 20/10/2020)

Note: This suits a Nextion NX4832K035 enhanced touchscreen.






3.5″ Nextion .hmi (updated 23/11/2020)

This suits a Nextion NX4832K035 enhanced touchscreen.
Whilst hmi file has images and fonts embedded, this zip contains .hmi, docs, images, and fonts.





Show your appreciation with a small donation

A small Paypal donation is always appreciated, and encourages development

To program your Nextion 3.5″ enhanced touchscreen:

• Unzip .tft file to a micro SD card
• Power down Nextion
• Insert card
• Power up Nextion
• Nextion should start programming
• Power down Nextion after “succeeded” message confirms completion
• Remove card


3.5″ Nextion HMI assests

Coming.  The complete Nextion HMI project with image files and fonts will be made available free !!!
Note: This suits a Nextion NX4832K035 enhanced display.
If you have a different Nextion variant, you will need to modify/debug the project yourself.
My advice:  Just buy a 3.5″ enhanced, and be done with it!  😉


5.0″ Nextion .tft

Coming. The larger 5.0″ 800 x 480px display offers a lot more room for bigger buttons, bigger fonts, and more presets.


5.0″ Nextion HMI assests

Coming.  The complete Nextion HMI project with image files and fonts will be made available free !!!
Note: This suits a Nextion NX8048K050 enhanced display.


Project PCBs

Will be available to purchase from the vk4ghz.com store.

Either blank, or populated to your requirements.


More to follow, so keep checking back here.


You can find me on the Radio Artisan Groups IO:  https://groups.io/g/radioartisan/


Subscribe to my YouTube channel where videos will be published: