| Original K3NG Issue | Repacked Solution | |---------------------|-------------------| | Paddle inputs share ground with high-current key line | Separate analog/digital ground with a ferrite bead | | No pull-up resistor values specified | 10k for paddles, 4.7k for I2C, 1k for transistors | | Display wiring changes with LCD type | Standardized on I2C (only 4 wires: VCC, GND, SDA, SCL) | | Sidetone output is just a pin | RC filter (1k + 10µF) + buffer transistor before LM386 |
Use a metal "mint tin" or aluminum project box to prevent RF interference from tripping the Arduino.
Add an LM386 audio amplifier circuit with a dedicated low-pass filter to turn harsh square waves into a pleasant sine-like tone. Human-Machine Interface (HMI)
Some sellers who offer K3NG-based PCBs include a detailed assembly guide with a repacked schematic. These are often worth purchasing because the schematic is tested and known to work with the PCB. k3ng keyer schematic repack
The K3NG Arduino CW keyer, designed by Anthony Good (K3NG), is a gold standard for amateur radio operators. While the open-source firmware is incredibly powerful, navigating its extensive schematic and hardware options can be daunting.
The standard K3NG schematic relies on a modular architecture:
Always start on a breadboard to test functionality before committing to a permanent PCB. | Original K3NG Issue | Repacked Solution |
To ensure a successful schematic repack, keep the following tips in mind:
Use the Arduino’s internal pull-up resistors, or add external resistors to the rail to ensure stable logic states. 4. User Interface Block
Have you created a K3NG schematic repack? Share it on Groups.io or GitHub with the tag #K3NGRepack. The community depends on your contributions. These are often worth purchasing because the schematic
Once the basic keyer is working, you can expand its capabilities using the K3NG code features. Display Modules
: If you want a cleaner build, consider using or designing a K3NG Keyer Shield that mounts directly onto the Arduino. Getting Started with the K3NG Arduino CW Keyer 1
When using the K3NG code for a repacked hardware build, you must edit the keyer_features_and_options.h file. FEATURE_COMMAND_BUTTON Enable: FEATURE_POTENTIOMETER Disable: FEATURE_LCD_DISPLAY (to save space and power) Disable: FEATURE_MEMORIES (unless you add extra buttons) Pro-Tips for a Clean Repack