Keyer Schematic Repack: K3ng

Assuming you’ve downloaded a repack PDF (see the resources section below), here is how to build your K3NG keyer without headaches.

If you experience erratic keying, ensure #define DETECT_PADDLE_PULSES is enabled to clean up dirty mechanical contacts on older paddles. 5. Construction Tips for Clean Keying

A simple piezo buzzer or a small speaker driven by a transistor to hear your Morse code locally. k3ng keyer schematic repack

Connect the common/shield of your paddle 3.5mm jack to the Arduino GND .

Directly connecting an Arduino pin to a vintage or modern transceiver can destroy the microcontroller due to high voltages or reverse currents. This repacked interface uses optoisolators for absolute safety. Assuming you’ve downloaded a repack PDF (see the

This version is typically built on an Arduino Nano and is perfect for a first-time builder. It forms the foundation for many of the more complex PCBs.

into more digestible hardware designs for specific builds, such as the Arduino Nano or Mega. Core Schematic Components Construction Tips for Clean Keying A simple piezo

The Arduino generates a square wave for the audio sidetone, which sounds harsh without a basic low-pass filter.