It is not difficult to add a 2.8″ TFT display to your existing µBITx. Make sure you order a 2.8″ ILI9341 touch panel display. These are readily available on eBay and AliExpress for under US$10, which is half the cost or less than a Nextion display. This display, however, has its downsides … more on that later.
Wiring changes required
Ashhar Farhan VU2ESE has clarified that on the new V6 mainboard, the connector to the Raduino has two extra pins. These don’t disturb the original configuration of the original connector, they bring the Keyer pin and the PTT from the Raduino to the main board to be routed to the keyer and the mic connectors. You could still plug in an old 16×2 LCD raduino into the new v6 main board and it will work all the same.
Pictures will be posted shortly.
It is recommended that you add a heatsink to the regulator on your Raduino board, as feeding the ILI5341 will result in additional current draw over the 1602 standard display.
Installing the new firmware
The factory firmware can be downloaded here.
Note that if you have a v3 or v4 board, the firmware will require a modification to change the IF oscillator frequency. This is because the v5 and v6 boards use a different IF filtering frequency (12MHz). Only one line of code will need changing. Which line? Anybody?
Upsides and downsides of this display
The upsides of the ILI 9341 display is that it is very affordable and supported by factory uBITx firmware.
The downside of this display, however, as can be seen on the demonstration video from HF Signals, is that it is very slow in operation. This is the result of the slow Arduino Nano processor having to communicate via serial port with the processor-less ILI9341 display.
The Nextion display mod from Ian Lee KD8CEC results in a much more responsive and attractive display, updating very quickly and being able to display S-meter readings and has other features not found on the v6. However, it does come at a greater cost.