Amateur Radio

Morse-it BLE Hardware CW Key

This project utilizes (at minimum):

  1. An iOS device with Bluetooth LE capabilities
  2. Morse-it
  3. Adafruit Feather 32u4 Bluefruit LE
  4. And a physical CW key of your choice.
  5. Various bits of wire and a micro USB cable
  6. Soldering iron and solder, wire strippers and other basic electronics tools.


  1. Update the firmware on Feather
    1. Easiest way is to download BlueFruit Connect
    2. Open the app, find the “Adafruit Bluefruit LE” device and click the “Connect” button
    3. Scroll down the list, find the “Update” menu option and install the latest firmware
    4. Download and install the Arduino IDE
      Firmware Update
  2. Follow the Adafruit Arduino setup guide to add the Adafruit boards to the IDE.
  3. Connect the board to the computer with a micro USB cable
  4. Create new project in the Arduino IDE
  5. Copy the 3 files from the project into your new project.
  6. Compile the project
  7. Upload the project to the board
    Arduino IDE
  8. Wire the CW key to the board. In my case I used an old mobile 3.5 mm headphones adapter so I could quickly move the key between the Bluetooth module and the radio. I used a 4 pin Dupont connector for quick connection to the breadboard. If you want you can mount the feather on a breadboard. You can order the board with headers already installed, I chose to solder the header pins myself.
    1. GND – Common on the CW key
    2. PIN A0 – Dit( . ) for iambic keys or for straight keys
    3. PIN A1 – Dah( _ ) for iambic keys
      Feather Wiring
  9. On your iOS device, go to “Settings” -> “Bluetooth” and discover “MorseKey”
  10. Open Morse-it, go the “Tap” tab and test sending.

I’ve programmed the Feather so that it sends only the default key mappings. I haven’t bothered to measure latency as it is imperceptible. If you do experience timing issues, toggle the “Reduce delays” option in the Settings>Global>KeyType, depending on how you send, this can improve the decode. 

Other uses include using it a logging devices and checking the quality of your sending while on the air.

To use a Straight Key:

In Morse-It, open “Settings” -> “Key Type” and select “Straight Key”.  This sets up Morse-It to work with a straight key.  Then go back one menu level and select “Hardware Interface” -> “Straight Key” under the “Keyboard” option at the bottom ensure that the “Enabled” toggle switch is green and then select “- Key” and set it to “Left Arrow”.  This is the standard configuration, if that doesn’t work, change “- Key” to “Right Arrow”. 

M7BVC tests out the finished project.

A huge thanks to the work done by Chris Young on his tutorials and GitHub page. This project is adapted and modified from his original work and is licensed under Creative Commons ShareALike.

One reply on “Morse-it BLE Hardware CW Key”

Joshua, great write up. I had ordered the ipac board to use with Morse-it. But now just ordered the Bluefruit LE. Thanks for putting this together and sharing it.

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