KB1OIQ Mods to BITX40 and uBITx – particularly for Blind Ops

Andy, KB1OIQ,  has uploaded his Arduino sketch files, photos, videos, and documents describing modifications he has made to his BITX40 and uBITX QRP transceivers to Sourceforge:

Andy has done extensive modifications to his hardware and software, so don’t blindly download these sketches and expect them to work!

It is his hope that constructors will be inspired to make these modifications on their own transceivers. He has used a large percentage of VU2ESE’s original code, and added quite a bit of his own.

Andy says …

“I have had a GREAT deal of fun doing this work, and I want to share it.”

Notable features for each rig:


  • keypad
    • Explicit speaking of mode, VFO, and frequency by keypad button press
    • Numeric frequency entry via keypad
    • common radio functions via single key press
  • RF gain circuit
  • software voice synthesis with Talkie library
  • standard ICOM MIC connector using UP/DN buttons and audio out (for digital modes)
  • fine tuning potentiometer
  • added USB (for digital modes)
  • save/restore rig parameters to/from EEPROM
  • audio mixer circuit so synthesized voice and “radio sounds” can be heard in one speaker


  • text-to-speech voice synthesis via Emic2
  • keypad
    • Explicit speaking of mode, VFO, and frequency by keypad button press
    • Numeric frequency entry via keypad
    • menu navigation
  • wired CW jack for use with either paddle or straight key
  • paddle supports left or right handed operation
  • converted LCD to I2C (requires Adafruit LiquidCrystal and SoftwareSerial, frees up 6 Arduino digital pins)
  • refactored the code into C++ classes (all text strings in PROGMEM)
  • reimplemented the menu system with the MenuSystem class
  • removed (perhaps temporarily) CAT and factory alignment to make room for other features
  • disable transmit if outside of USA ham bands
  • CW mode with correct frequency display
  • VFOs are saved/restored in/from EEPROM (mode and frequency)
  • Text sent to the LCD is simultaneously spoken by Emic2
  • Extensive menu selections
  • Several visually impaired amateur radio operators are interested in this work!  I am excited by the possibilities.

Andy has a long list of things still TO DO on his uBITX.  His current plans include:

  • keypad
    • decide which features to add to individual keys
    • currently: frequency input, speak radio settings, menu mode
  • RF gain circuit
  • AGC circuit
  • anti-POP circuit for TX/RX transitions
  • fine tuning
  • test and perhaps tweak RIT
  • add MIC and signals for digital modes at the MIC connector
  • USA 60m channels to memory for easy user recall
  • TBD other features that might be useful to visually impaired operator
  • split mode
  • if memory allows, put CAT control and factory alignment routines back into the sketch

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