HF SIGNALS started shipping the μBITX boards (or micro BITX) December 2017. This is a a fully wide-band 3 to 30 MHz transceiver with upper and lower sideband and CW, power up to 10 watts and solid digital control. The circuit boards come wired and tested and with all the hardware. An interesting component of this radio is the Radino. This board has a Arduino Nano controller and a Si5351 for all local oscillators.

Radio Description – http://www.hfsignals.com/index.php/ubitx-circuit-description/

uBITX Net – great source of uBITX information.

groups.io has a group for the varies BITX projects.

Wiring Up

I chose not to use the plastic case that it came with or to print a 3D but instead purchased an universal enclosure from Amateur Radio Kits (INKITS). It took 6 weeks deliver, which was not unexpected.  These things take time and worth the wait, The case is excellent value. Metal and came with additional installation hardware including PCBs for the external connections.

uBITx wiring – http://www.hfsignals.com/index.php/ubitx-wire-up/

Case Manual – https://groups.io/g/BITX20/files/UBITX%20CASE%20MANUAL%20%20PCB%20FRONT%20PANEL.pdf

uBITX Net has a list of updates to make.

Initial build photo below. Have added additional wiring for ground issues and wired in USB interface. Will get a photo next time case off. Will be soon enough 

Wiring 003

 Digital to the Left, Analogue to the right. Pin 1 to the left


Update – VU3SUA case documentation –  https://ubitx.net/2018/08/03/vu3sua-case-documentation/

Used the front panel board that came with the case. Proved to be convient and tidy but still not without its challenges. You will need to follow Sunil Lakhani on facebook to gain pictures of the boards, assembly tips and info for the board

Wiring 002


The encoder is not straight through.   

1<->1,2 <-> 4,3<-> 3, 4 <-> 2



CW Paddle

You need to add two resistors to support a CW paddle. Follow the directions on uBit.net.  

PaddleModFirmware Upgrade

Worked as advertised. Again checkout ubitx.net – http://ubitx.net/compare-software-options/ 

Decided to go with KD8CEC firmware – http://ubitx.net/wp-content/uploads/2018/04/ug1072_087.pdf

Get the latest from https://github.com/phdlee/ubitx

Install Arduino software, if not already installed. Install the USB drivers for the Arduino compatible board (CH340 serial interface) used by Radino for MacOS here 10.9+ or here 10.12.

Download the firmware files from GitHub, compile and upload to the Radino.

Bingo so now you have a HF  full source code for the HF transceiver on your computer. That is cool in initself. 

I ended up running version 1.08. Manual – http://ubitx.net/manual-kd8cec-firmware/


The board is v3. I want to address the T/R click noise and add an CW Audio Filter. Also saw pcbs for filters based on Glenn VK3IL’s blog.

Nick VK4PLN uBITX Add-On boards – https://vk4pln.blogspot.com/2018/03/vk4pln-ubitx-add-on-boards.html

Kess ND6T uBitX Add-On boards – http://www.nd6t.com/index.htm and ordering instructions in BitX20 group.

To Do


Calibration of these devices appears to be a black art;




I still have noise UBitxAudio.m4a when using the speaker. Headphones are Ok. It appears too be a Ground Loop problem.

Deployed common ground via a star config which improved the audio however still have the noise when using the speaker.  


Current solution is to stick to headphones and use the device.

Update 03082018

Updated the pic to show grounding. The brown wire goes to the common on front panel board. Still noisy.

There is a lot of information as to audio available uBitx.net and iGroups.


This is a fun radio.It’s cheap, it works and requires very little skills to  get operational.

Think will source another board. The uBitX v4 boards have no Audio IC On the board. 



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