: A piezo buzzer or a filtered audio circuit for a pleasant sidetone. Optional Modules
| 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 | k3ng keyer schematic repack
The K3NG Arduino Keyer, designed by Anthony Good (K3NG), is arguably the most powerful and versatile Morse code keyer available to the amateur radio community. However, because it is an open-source project with a massive feature set, the "standard" documentation can sometimes feel like a scattered puzzle. : A piezo buzzer or a filtered audio
The strength of the K3NG project lies in its inputs. A repacked schematic unifies the paddle inputs ( Dit and Dah ), the straight key input, and the function buttons into a neatly organized input matrix. Crucially, the repack addresses the analog inputs, specifically the speed control potentiometer. In a repacked design, careful attention is paid to the voltage divider network to ensure smooth linear control of the CW speed, often incorporating debouncing capacitors that may have been optional in earlier loose schematics. Additionally, the display interface—whether a standard 16x2 LCD or an I2C OLED—is integrated with the necessary contrast adjustment trimmers or pull-up resistors, ensuring that the visual feedback system is "plug and play." The strength of the K3NG project lies in its inputs