K3ng Keyer Schematic Repack ((full)) Jun 2026

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

| Component | Original Configuration | Repack Configuration | Justification | | :--- | :--- | :--- | :--- | | | Arduino Uno Board | ATmega328P DIP-28 | Size reduction, onboard integration. | | Regulator | USB 5V / Uno Regulator | LM7805 / LDO (TO-220) | Robust shack power input (12V). | | Keying Output | 2N2222 Transistor | PC817 Optocoupler | Isolation from rig HV/RF. | | Display | Parallel LCD (HD44780) | I2C Backpack (PCF8574) | Pin conservation. | | Input Protection | None | 10k Pull-downs + 0.1uF Caps | Debouncing and RF filtering. | k3ng keyer schematic repack

So go ahead. Download a repack, breadboard the circuit, upload the firmware, and tap out your first “CQ CQ CQ DE YOURCALL.” The bands are waiting. Assuming you’ve downloaded a repack PDF (see the