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.


Dimming your Nextion display

Ian KD8CEC has been looking at power consumption on the Nextion display and how to effectively dim the screen for portable µBITx work, where you want low current drain.

The following picture show’s Ian’s display (2.8″ TJC Chinese version) at Full Power:

And the screen fed with a series 50 ohm resistor (1/2 watt rated or more):

The slightly dimmer display halves the current consumption from 89mA to 44mA with a series 50 ohm resistor (made up of two 100 ohm resistors in parallel (or 3 x 150 ohm resistors in parallel).  The Nextion screen has a built in software dimming function, and this can be adjusted in Ian’s Nextion display firmware.   However, the feature generates noise in the µBITx and is not recommended.

Resistor installation

Installing a series resistor (with a value between 20 ohms and 100 ohms) in the +5V power lead will cause the display to be dimmed, but function normally (except for use of the micro-SD card reader).  The resistor could be installed across a slide switch or toggle switch (with one pole shorted and the other going through the resistor) to allow for two settings (normal, dimmed).   This could be handy for night time or portable use.  The circuit diagram for this is as below:

For further details see Ian’s website.

Nextion Displays – Hints for loading display firmware


Michael VE3WMB brings us some hints when installing Nextion displays:

1) The Display wants the microSD card to be formatted as FAT32.   Make sure your microSD card is no larger than 32GB

The default in  Windows is to format cards > 32 GB as exFAT, which the Nextion will not accept. In fact Windows 10 probably won’t even let your reformat a card this big as FAT32.  (I am sure if you dig deep enough there might be a way to do this. I am not a Windows GURU).

Currently you only need a 2 GB card,  so if you need to buy one for this purpose try an 8GB card.  It is also worthwhile buyong a brand name card (like Sandisk).
Some no-name cards are slower than cold molasses to read from and write to.

2) If you have a problematic microSD card, when you power up the rig you might not see anything on the display, not even a backlight !  

I spent considerable time trying to solve what I thought was a wiring/power problem to the display when it was a bad SD card. When the I removed the card and power-cycled the rig the Nextion display came up fine with a demo program that was already loaded.  So my recommendation is for the initial power up of the display don’t insert the SD card. That way you can be sure that you have it wired up ok before you start messing with SD cards.

3) Beware, ground and +5V connections on the Raduino going to the Nextion Display are adjacent to each other. 
I recommend that you check and recheck your wiring several times before applying power.  It is very easy to accidentally swap these and you won’t be happy if you do.  As they say, “An ounce of prevention is worth a pound of cure”. One group member has already found this out the hard way.

Mark AA7TA adds:

4) Duplicate .tft files (including hidden files) will cause grief on the Nextion

You may get a message on the display that the load failed because there is more than one .tft file on the SD card.  This can happen even when you look and you see only one file.

You need to be sure to enable viewing of hidden files in file explorer (Windows) or finder (on a Mac)… There’s probably one hiding there with the .tft suffix that you need to delete.  I don’t think either operating system will show hidden files by default. The same goes for Linux.

Mark notes that a 1G SD card is plenty big enough for the current tft file.

Keven adds, “Linux doesn’t show hidden files by default.  But you can see them by typing:

ls -al

in a terminal window when you’re in the directory you want to examine.  To hide a file, rename it with a dot (‘.’) as the first character.”

Mike ZL1AXG adds:

5) Make sure you install the screen the right way around

Power up the display before you start making holes and check the orientation of the display and that the screen is functioning correctly.   As with the 16×2 display, it is possible to install the display upside down by mistake!  Given it is not symmetric (there is a wider bar to the right hand side of the display) care is needed!  The inner silver line on the screen defines the touch sensitive boundary.  Cut your hole so that the screen fits so the line is just visible around the outside edge.

Dimensions of Nextion displays can be found for this zone on the itead website. Click on your display and near the bottom of the page you will find a link to the screen dimensions.

6) For most people the 3.2″ screen or larger will be best

A 3.2″ screen is only just big enough to feel comfortable for us fat-fingered chaps.   It is also just wider enough to reuse the width of the 16×2 screen.  Smaller screens inserted in the space where the 16×2 screen currently lives will require an additional aluminium or plastic plate to be added to the front panel to cover the existing width of the 16×2 screen.


New graphic for

Some of you will have been sufficiently observant to notice that the graphic at the top of the webpage has been updated.  This is because Mike ZL1AXG has installed a Nextion 3.5″ touch screen on his own µBITx.    Careful work with a drill and file will yield satisfying results.

He also installed the latest pop fix from the v4 board (see the separate article).

Nextion Displays – Current draw

Lowell has tested current draw on a 2.4″ and a 3.2″ Nextion display following questions from constructors over the likelihood of cooking the existing 5V regulator.  With a supply voltage of 5.04 VDC, the 2.4″ display drew 125 ma. and the 3.2″ display drew 110 ma. Both  displays were at full brightness.   While the figures are slightly above those listed on manufacturer’s website, this suggests the 5V regulator should be fine.   If in doubt, add a heatsink!


KD8CEC releases CEC Beta firmware to support Nextion display

Ian Lee KD8CEC has released Beta firmware for the µBITx that supports Nextion colour touch screens .  He has also released matching files for installing firmware in the Nextion displays for 2.4″ and 2.8″ screen sizes.   No programming is required to use these displays.

The photo above shows the touch panel display.  Pressing on the screen will perform functions like changing band (up/down), changing frequency, adjusting the Attentuator (ATT), IF Shift and RIT, and going into Split mode.

See Ian’s webpage for details about downloading the various firmware options along with detailed instructions.

Buy your Nextion display now!

If this display looks like it is from a commercial rig, then you are wrong!  It is  the Nextion display mounted on a µBITx!

Ian KD8CEC will shortly release his newest enhancement to CEC firmware.  His latest modification to the CEC firmware supports Nextion screens. This was foreshadowed recently on the BITX20 list.


If you want further proof, check out Ian’s recently prepared youtube video of the Nextion screen in operation.  His release is imminent.

Get your order in for a Nextion display immediately, as they are likely to sell out when 6000 µBITx owners twig that they really do NEED a Nextion display.  [Note that has no relationship with ITEAD – who make the Nextion!]

Why Nextion?

There are some very good reasons why the Nextion display is the way to go:

  • Nextion screens make it quicker for developers to provide a user-friendly interface to their product:  a separate processor controls graphics on the screen, and a Windows WSYWIG emulator can be developed for free to whip up a User Interface for the Nextion display.   The processor in the Nextion has its own control language and coding that is similar to C++
  • Users can easily hack their own display’s look and feel, by plugging into a standardised protocol between the screen processor and main processor that are connected via a standard serial port.
  • Screens come in a variety of sizes from 2.4″ to 7″.  Resizing of images and buttons is all that is required to make firmware work on a different screen size. No coding is required.  Software required is simply the Nextion Windows software and a graphics programme (MS Paint is adequate).
  • The screens come in two varieties:  a BASIC model and an ENHANCED model.  The ENHANCED model has GPIO lines controlled by the display processor and a Real Time Clock (RTC).

Nextion display units cost more than other displays for a reason.  The independent processor removes most of the burden for screen manipulation from the main processor, and it is much quicker and easier to develop the user interface and to customise it for different sized screens and to add/subtract features.   Nextion displays also include a microSD card reader.  They run on +5v DC and include a serial port.   Note that the Enhanced Model contains a battery mount for the RTC, but does not include the battery (CR1220) itself.  This is not required until you want to use the RTC.

How easy will it be to use the Nextion Display?

It will be VERY EASY to add a Nextion display to your µBITx.  Watch the video!

No hardware modifications are required to your µBITx, but you will of course  need enough front panel space to install your colour touch display of choice.  You may even need a bigger case if you want to install the 7″ Nextion display!

You will also need to download two new files:

  1. an updated version of KD8CEC’s firmware, that incorporates the interfacing protocol to the Nextion for installation in your Raduino.
  2. an image file (firmware) for insertion in the Nextion display unit.

The downloaded firmware for the Nextion needs to match with your screen size.  There are two variants for each screen size:  a BASIC or ENHANCED version of the Nextion display unit (see the discussion on which version to buy below).

This firmware needs to be saved to a microSD card (a 2GB or larger card is required).  Insert the card in the Nextion display and in powering up the Nextion display will automatically load the firmware from the microSD card into the Nextion flash storage.   Remove the microSD card when the upload is complete.

Four wires connect the Nextion display to the Raduino.  Two lines are for power, and the other two are serial RX and TX that connect to standard IO ports on the µBITx that were used for the 16×2 standard display.

Reboot your µBITx and your Nextion display should be working!

What to look out for when buying a Nextion Display

There are two versions of the Nextion Display – one developed for the Chinese market and an English language version that supports the Nextion Windows development environment.  Make sure you don’t get the cheaper, but incompatible Chinese version.  Look out for “English Version” in the marketing blurb.  This won’t be an issue if you buy from the developer (ITEAD).

 I understand a downloadable hex file will be available that works the same as the English version, for those of us who purchased the wrong model in error!  Thanks to Ian, who did it blind (also not being able to read Chinese)!

Any size will work with the CEC firmware on the Raduino end.  However, Nextion firmware is specific to  either the BASIC or ENHANCED version of the screen and to the resolution of the screen.   That said, any version can be modified to work with any other screen size with just a little bit of work on the part of the user.   You can also fully customise your screen to meet your own requirements.  Change the colours, or change the entire look and feel.  No coding is required to do this, just cut and paste the code from the supplied CEC version for each tool.

Purchase the ENHANCED model of the Nextion (for a few more dollars) if you think you will use the GPIO or RTC features in future.  The RTC could be useful for digital modes that require precise timing, or for satellite work, etc.  Additional GPIO lines could solve one of the problems with the Raduino:  a lack of spare digital ports to support customised add-ons.  For example, if you want to add 160m and switch in an additional LPF, or  if you are worried about potential spurs, you will be able to pull in bandpass filters for the high bands. In these instances you may want to spend a little more to get the ENHANCED version.

If you don’t want to wait until firmware is available for your screen size, then purchase a 2.4″ or 2.8″ BASIC or ENHANCED Nextion Display now.   These two screens have the exact same resolution, and the default version of the Nextion Firmware from Ian KD8CEC will work on both screen sizes without modification.

If you already have a different sized screen, or want to buy a bigger screen, right from the outset, don’t panic.  You may need to make some adjustments to the firmware yourself.  This is not difficult – but involves resizing graphics and moving around objects to suit the larger screen area/resolution.  Some of us are working on modifications to the Nextion firmware to accommodate 3.2″ and 3.5″ screens. Firmware for these screens is likely to be available quickly.

Screen sizes and resolutions for the BASIC models available on ITEAD’s website are as follows:

The ENHANCED versions available from ITEAD are as follows:

Most of us will choose to buy our Nextion displays from Aliexpress or eBay.

They are available in all sizes and in either BASIC or ENHANCED versions.  It is unclear which are OEM versions and which are clones.  It probably doesn’t matter.

Look for highly rated suppliers and those with higher shipping volumes.  The biggest risks are that your screen arrives cracked, or simply never arrives.  You will need some form of redress when goods arrive in a damaged state or simply never arrive, and this is where the intermediaries in eBAY, Aliexpress or Paypal can assist.


Latest release of the TFT Colour Touch Control from VU2SPF and VE1BWV

VU2SPF and Joe VE1BWV have released the latest version of their TFT Colour Touch Control.

Low cost, standard easy to get parts, Colour, Touch Control and any combination of Touch Control or physical buttons.

TFT (Touch) Display module, Atmega 2650, Si5351 DDS, 1 UBITX and a few wires = All Band rig with Computer / Radio Touch Control Colour Display.

Some new features:

  1. Automatic Scanning – up to band edges in both the directions is now added in V2.9bU of software. The scanning allows one to find signals of interest across the band. Two small buttons labeled ‘U’ and ‘D’ scan in up and down directions from the currently set frequency. The scanning can be stopped by touching the frequency display area.
  2. CAT Control  – the software now has new code to emulate FT817 Cat commands… This provides radio and computer control for the digital modes.
  3. User Manual   A new comprehensive user manual has also been added. Various users and new builders have been looking for this for quite a while.The new version is available on Github at : also available at:

(UBITX ver2.9bu Installation Results)

Note that at present the firmware doesn’t support CW.


Nextion Display and KD8CEC firmware

Ian KD8CEC is working on a protocol to allow Nextion LCD touch displays to communicate with the µBITx.

He is implementing this a little differently to most support for Nextion LCDs.

The firmware will handle communication between the uBITX arduino and Nextion LCD using template files.

There are quite a few variables in the Nextion LCD. If the status of any parameters in the uBITX changes, the variables sent to the Nextion LCD will also be changed at the same time (and vice-versa).  This should allow any Nextion display and any configuration of the display’s User Interface to interact with the µBITx.  This means constructors can customise their µBITx display using the Windows GUI used with the Nextion to configure the “look and feel”.

For example, when uBITX’s frequency changes, it is transferred to a specific variable on Nextion LCD.

Example code


Below is an example of simple frequency and mode display changes






















JackAl is here!

Jack W8TEE and Al AC8GY have  released details of the JackAl board following FDIM (preceding Dayton Hamvention).

Friday night is a sort of Show-and-Tell at FDIM and they used that opportunity to show their JackAl board in action. The photo above shows a little more about what it is and does.

At the show, Al hooked up a noise generator to the µBITX to show how the filters work. (There are 4 preset filters for CW and 4 for SSB.) In addition, you can customise one CW and SSB filter to the bandwidth you desire. You might be able to see that the skirts are pretty steep for the filters on the scope in the background. The setting of the CW custom skirts are set differently, in that you pick a centre frequency (e.g., 700Hz in the shot below), press the encoder, and then you see this:

In this case, turning the encoder CCW increases the bandspread (i.e., the 440 red number above, although it looks orange in the photo) by simultaneously moving the skirts (480Hz and 920Hz) further apart. If you turn the encoder CW, you narrow the bandspread. Most CW users will probably center the bandpass on their favorite sidetone frequency, which centers the bandpass on that frequency.

The demo used a 5″ display, although a 7″ display is also available. The third knob on the front is for a second encoder that we use for everything from setting the CW keyer speed to adjusting the filter skirts. You can see some of the plots on the panel at the rear of the picture above for some of the board’s features (e.g., filter responses, compression, etc.) Those will be included in the documentation when the (downloadable) manual is finished.

The JackAl board has the following features:

  • 5″ or 7” touch screen 800×480 TFT color display
  • Dual VFO’s
  • RIT
  • S meter
  • RTC
  • CW keyer, 5 to 50wpm (we could go up to 100wpm, but…really?)
  • Up to 50 CW preset messages, selectable at runtime…perfect for contest messages
  • Touch screen function and control selection (e.g., band changes, RIT, mode, VFO, VFO increment, LSB/USB, etc.)
  • Automatic LSB/USB selection based on frequency (overrideable)
  • One touch frequency increment changes (1Hz to 1MHz in multiples of 10…the white underscore in the frequency window)
  • Dual encoders (frequency, features)
  • EEPROM storage of user preferences (one-click reset to “factory” defaults)
  • Uses Teensy 3.6 processor (1Mb flash @180MHz) and companion audio board
  • Support for 3 external CW push button switches (NO) for sending stored CW messages (e.g., contesting)
  • Hardware AGC using IF take-off
  • Audio AGC with adjustable threshold
  • Mic compressor with adjustable threshold
  • 8 band audio equalizer
  • Receive audio filter: 48dB/octave (8 pole equivalent DSP filters)
  • 4 CW presets (150, 300, 400, 600, [or none] Hz 3dB bandwidth) + 1 user-defined knee frequencies (at runtime!) filter
  • 4 SSB presets (1500, 1800, 2200, 3000, [or none] Hz 3dB bandwidth) + 1 user-defined knee frequencies (at runtime!) filter’
  • Variable Notch filter, encoder adjustable, use specified Q
  • 7 watt power amplifier

The board will be distributed with all (surface mounted) parts in place. The user must supply the Teensy 3.6 ($30), its supporting audio board ($15), and the 5″ ($34) or 7″ ($44) touch screen displaying (using the RA8875 controller chip,

We expect the JackAl board to sell for $50.

We may need to adjust this price as we have only received “ballpark” cost estimates for the board since we only have the Gerber files for the Beta board.

Currently, we are using less than 20% of the available flash memory (out of 1Mb) and less than 15% of the SRAM (256K), so there is plenty of memory resources available for adding “stuff”. The board also brings out a number of I/O pins to help your experimentation. With the exception of removing one SMD resistor on the µBITX board and soldering two wires to those pads, all interconnections are via existing connectors.

Our best guess is that after finishing the modified Gerber files, production, Beta testing, and writing support manuals, it will be probably two months before we begin distribution. We will announce its availability here as soon as we can. BTW, if anyone knows a high-quality PCB manufacturer who also does pick-and-place at reasonable prices, we are getting quotes and would like to know about them.