SOTABEAMS make a Digital Variable Audio Filter Module that could usefully be added to your uBITx.
Dennis KG4RUL has developed an Arduino sketch for the SOTAEAMS Vari-filter which includes a nice display. It utilizes a USB Nano V3.0 ATmega328 16M 5V Micro-controller CH340G board, or similar, available from Amazon and other sources and an OLED display module such as the HiLetgo 1.3″ IIC I2C Serial 128×64 SSH1106 OLED LCD Display LCD Module for Arduino AVR PIC, or similar.
Dennis is happy to share his firmware, but cannot offer any support – so please do not contact him for support.
You can download the sketch and a schematic, in PDF, from the SOTABEAMS website:
An additional document supplies information for linking a microcontroller with a SOTABEAMS, VariBeam (VB) module for use with a BITX/uBITX. You can access this file at the following URL: