Nextion Firmware for 3.2″ and 7″ screens

VE1BWV(Joe) and KN4UD (Allen) have  announced the release of Nextion firmware to support larger screen sizes with KD8CEC firmware v 1.094 and up.

The current releases include support for the 3.2 and 3.2E and for the 7 inch Nextion display.

The screens have been redeveloped with new buttons  and enhanced graphics to reflect each of the 2 display sizes.   This work is on going but due to high requests they have decided to release current versions which are fully functional and utilise the full display area.



Updated Nextion firmware v1.095 beta

Ian KD8CEC has released an update of his µBITx firmware and accompanying firmware for the Nextion display (for 2.4″ and 2.8″ displays).


Others are working on resizing the firmware to work on 3.2″, 3.5″ and 7″ displays.  It would be simple to also convert the 7″ firmware to work with a 5″ display.

So what is new in this latest beta release?

  • The buttons are more reliable, and are quicker to take action.  Changing mode was a bit of a slow process with lots of flashing buttons in previous versions

  • Pressing on the step size now opens up buttons to select step value.  This makes it so much quicker to get around the band.  Select a bigger step value to get to where you want to go, and switch back to 1Hz steps to fine tune.


  • By selecting which file you download, you can now read/write to all EEPROM memories or just those that relate to the Nextion display, protecting your rig’s settings securely if you want (the only way you can change them is in uBITx Manager if you go with this option).

  • Adjust the frequency by pressing on different sections of the frequency shown on the Nextion display
  • The lock button locks the Nextion screen as well now which is handy for using your rig around young children.
  • The sleep function has been improved.  You can wake the screen up by moving the encoder dial, or pressing on the bottom left of the screen.

  • Install two screens – they will each mirror what happens on the other, but in some modes different functions can appear
  • A number of enhancements to the control menu, including an elementary spectrum scope, band scanning and memory selection, saving.

The pace of development is pretty staggering.  We all look forward to other functions being added to the Nextion screen in future!

To download these beta files check out Ian’s article.

Analogue S-meter using a VU meter and driver module

Jean-Luc F6HOY added an analog s meter to his first BITx40 with a simple circuit on an audio line and a 500 microA vu-meter.  All was fine except that without any AGC it only provided an indication of the signal level.

Jean-Luc added a Chinese Audio Vu-meter that is much better on his µBITx.
For around 15€ he received a circuit module and 2 vu-meters.   Only one vu-meter is used of course.   The circuit board functions as an AGC, and for an extra bit of fun he has a nice warm light in the shack from the yellow light of the VU meter.

You can get this kit from several shops in China (one such  example).


Belt and braces filtering of a BITX40 power supply

Akira JJ1EPE had spuries on his BITX40 at 75kHz.

The modification for suppress the spurious signals provided by a friend involved the following steps:

1) Add 3.3uF electrolytic capacitor to VCC line of Arduino board


2) Add 0.1uF x 2 bypass capacitors to the VCC line (fuse point)

3) Insert high frequency choke of about 100 uH in the power line of Arduino

4) Connect the minus line of power supply line to the ground

5) Connect the minus line of BITX40 main board to the chassis ground

6) Add 0.1 uF × 2 bypass capacitor to VDD of BITX 40 board

7) To prevent common mode noise, add 0.01uF x 2 bypass capacitor to the power connector

This series of steps could equally well be applied to the µBITx if you have noise from your power supply and want to get rid of it with a very thorough strategy.


An amazingly smart idea for extra I/O ports

Tom WB6B want to expand the number of digital and analog I/O pins available to him in adding enhancements to his uBITx.

He came up with an ingenious idea, by creating a Smart LCD Backpack to replace the commonly found ones on inexpensive 2×16 and 4×20 I2C displays found on eBay and Amazon.

He has uploaded a library to GitHub that allows you to program a Arduino Nano to emulate the common I2C to parallel backpack used on an I2C display (either size). The Smart I2C Backpack, additionally, allows you to read and write the analog and digital pins on the Smart I2C Display Backpack.

The package includes a interface library that you include in your code to interface with the Extended I/O functionally. Also included are two example sketches. One is the code you program into the smart backpack. The other is a demo/test program you program into another arduino and connected via the I2C bus to the Smart Backpack Display.

The Smart Display Backpack should work with firmware using standard I2C LiquidCrystal drivers such as the KD8CEC firmware.

The code uses libraries that are installable from the Arduino library manager,.  The GitHub URLs are just for reference.

The following libraries should be part of the base Arduino software install:

  • Wire
  • LiquidCrystal

Tom hopes that others will enjoy this new display and I/O expander.

And the link to the code …


Adding the v4 pop fix directly to a v3 board

Nigel G4ZAL has added the v4 pop-fix to his v3 board by placing components directly onto the v3 board.


  1. Swap out R70 from 100 ohms to 1K.

  1. Drill a small hole (0.7mm or similar) to the right of R70 so as to be able to fix the 2N7000 transistor.
  2. Pin 2 of the 2N7000 is soldered on the underside of the board (ground).
  3. Scrape a little varnish from the tracks and tin ready to fix the 2N7000.
  4. Add some Kapton tape to stop any shorting of components.
  5. Add the remainder of the components and run a bit of enamelled wire to the trace near the Raduino headers to pickup the T/R line.

Seen from the front of the main board (ignore the cutouts on the front of the board)


Homebrew uBITx with through hole components

Peter M0HYT likes to do it the hard way.  He has designed a circuit board layout with the Nano on board and stocked with traditional through hole components.   You will see his new board photographed alongside a uBITx kit main board from HF Signals.  It looks pretty stunning!

Download the design details:



Getting prepared for the JackAl

Some of you are waiting with baited breath for the JackAl Board, announced by Jack W8TEE.   You can get yourself geared up for the JackAl by pre-purchasing some of the kit required, as it is due to be released shortly.  You will need a colour touch display panel, a Teensy 3.6 processor and associated Teensy audio board.

Display panel

There are two display options for the JackAl board: 5″ or 7″.  Neither is likely to fit in your existing µBITx enclosure, so you may also want to purchase a new enclosure.

The panels can be purchased from Their order numbers are:

ER-TFTM050-3 (5″)
ER-TFTM070-5 (7″)

Both displays use the following options:

4-wire SPI interface
Resistive touch
No font (the library is being used for fonts)

Both are 800×480 displays using the RA8875 chip. If you run the samples using a touch screen, make sure you run the Calibration sample program first.

Teensy 3.6 and audio board

The Teensy 3.6 and its associated audio board can be purchased from the manufacturer’s website or from other sources.


MicroSD reader extender

Rohn KR0HN  was “parts shopping” online when he came across a microSD card extension cable.

This could be used to extend the microSD card slot of the Nextion display out to the exterior of the case.  This would be handy for upgrades to the display firmware as new features become available for your display.

The link to the amazon page is: