CW Coders

A group dedicated to the scientific exploration and open development of Interrupted Continuous Wave and Morse Code Telegraphy.

As a community we explore the computer science, electrical, electronic and radio-frequency engineering concepts covering all aspects of CW equipment and operation.

The practice of CW operation is a deceptively complicated area that offers much to explore. On the surface it seems rather straight foward. Morse Code is perhaps the simplest method of encoding language and the single-frequency interrupted carrier-wave is the simplest of rf transmission modes. Together these two simple concepts significanly constrain the core requirements.

However, once solutions start to involve electronic keyers and microcontroller / computer software the domain rapidly expands to include many of the most interesting and challenging aspects of Human/Computer interaction. The real-time nature of events and the coupling of both input and output elements result in requirements that are usually only required by electronic musical instruments. Not even modern video game controllers require the time-domain resolution that our devices require.

As with all aspects of engineering and highly-technical applications there is an abundance of different methodologies and solutions available. This is especially true when it comes to learning methods. In our group we respect all attemtps to solve the challenging problems we face. We'll strive to catpure any relevant resources and approach our catalogging and discussion all existing and emerging solutions without bias. Innovation and experimentation is especially encouraged.

Initial interersts and objectives include:

  • Learning

    • Pedagogy of Learning Morse Code
    • Techniques for teaching/learning/mentoring
    • AI inspired learning techniques
  • Resource Catalog

    • Key Types
    • Language/Grammar of Morse Code
    • Existing Keyer Implementations
    • Learning Resources
    • Learning/Teaching Clubs/Institutions
  • Keyer Software

    • Abstraction Layer Model
    • Universal Software Library (Portable Code; C and/or Rust)
    • CW Signal Extraction and Digital Decoding
    • Keyer Modes
  • Keyer Firmware

    • Port examples of hardware abstractions
      • ESP32S2
      • ESP32S3
      • Arduino
      • Raspberry Pi Computers
      • Raspberry Pi Micros (RP2040)
  • Interconnect

    • TCP/IP network Protocol/s
      • Interface/Configuration
      • Internet Relay Services
        • Channels
    • USB/Serial Protocols
    • Key Event Protocols (Original Key/Paddle timing events)
    • Human Interface Device Protocol
  • Hardware

    • Single / Dual Pole Keys
      • Straight Key
      • Single-Lever Dual Pole
      • Dual-Lever Dual Pole (Iambic)
    • Sidetone / Oscillators
    • Tx Output Key / Isolation Circuits
    • Debounce
    • Screen/LCD
    • Microcontroller References / Reviews
    • Schematic / PCB Layout / EDA
    • Measurement and Performance
      • Minimum Key response-time / Max WPM accuracy
      • Key to Tx response time
      • Jitter


K3NG ardunio keyer [Github]

An open source Arduino based CW (Morse Code) keyer with a lot of features and flexibility, rivaling commercial keyers which often cost significantly more.

K3NG Pic Keyer

Simple PIC Keyer from K3NG.

Vail Adapter


CW Hotline


W8BH Morse Tutor Chez VE6LK Kits

Very similar to the Morserino below.

Morserino [Github]

A multi-functional Morse device (Keyer, Trainer, Decoder, even Transceiver etc.). It is ideal for learning and practicing Morse code, useful for everybody from beginner to high-speed pro.

K1EL K16 Keyer IC

PiCW - ykaw

A morse code keyer running on Raspberry Pi.

The CWC Commuter

A little box that you can plug a key and headphones into. It Wifi connects to your phone hotspot. It has a channel selector. Dial up a channel and tx/rx CW on that channel. That's it.

This is an internet transceiver for CW that you can take with you. It aims to be more like a radio than a computer.


Enables you to get a wide view of the different keying modes, to compare their proper logic and accurate timing with the logic and timing of other keyers

YACK - Yet an other CW Keyer Source Files

YACK is a universal CW keyer library and application for the AVR architecture.


This is a tiny, cheap, and open source CW keyer. (ATtiny*5)


This is an iambic keyer based upon the Arduino UNO platform. It provides a means to generate audio sidetone for the purpose of implementing modulated FM that can be used on 2M repeaters.

PiCW - JamesP6000

Raspberry Pi bareback LF/MF/HF/VHF CW (Morse code) transmitter

Makes a very simple Morse Code transmitter from your RasberryPi by connecting GPIO port 4 to Antenna (and LPF). Operates on LF, MF, HF and VHF bands from 0 to 250 MHz.

Compatible with the original Raspberry Pi, the Raspberry Pi 2/3, and the Pi Zero.


This is an "Accu-Keyer" (WB4VVF) Clone for the Arduino (or ATTiny45 or 85)


Joystick becomes a CW key.


A reboot of the original DigiKeyer.


CW Academy

Long Island CW Club

CW Innovations


Morse Code Ninja [Github]

Morse Code World

Learn CW Onine

G4FON Koch CW Trainer

Learn Morse Code - ARRL

W1AW Code Practice Files

K1USN - CW SST "Contest"

CW Internet Relay

Hamradio Solutions provides both hardware and network chat services.