Keyer Schematic Repack — K3ng

: These are the most common "repacks" that bring the keyer's powerful features to life on a single PCB.

A schematic repack is only as good as its matching keyer_settings.h and keyer_features.h files. When flashing your Arduino with the K3NG source code, ensure the following definitions match your repacked hardware:

Use on the keying outputs to prevent Radio Frequency Interference (RFI) from crashing your microcontroller. 2. Essential Circuit Modules k3ng keyer schematic repack

Over the years, several variations and upgrades have been made to the original K3NG keyer schematic. Some of these modifications include:

Arduino Nano v3 (highly recommended for stability) PDF 1.2.5 . Transistor: 2N2222 or BS170 (for keying output). Resistors: 1k Ohm, 10k Ohm, 2.2k Ohm. Capacitors: 0.1uF. Other: Paddle jack, Piezo speaker, 10k potentiometer. The Basic Schematic Diagram : These are the most common "repacks" that

When assembling your repack PCB or stripboard, use this standardized pin mapping reference based on the default K3NG configurations: Arduino Uno/Nano Pin Arduino Mega 2560 Pin Input (Analog) 10k Linear Pot Command Button Input (Digital) Active Low (Internal Pullup) Dot Paddle Input (Digital) Add RF Bypass Cap Dash Paddle Input (Digital) Add RF Bypass Cap Transmitter Key Output (Digital) Connects to Optocoupler PTT Output Output (Digital) Optional Amp Sequencing Sidetone Out Output (Digital) Square wave output 4. Firmware Configuration Checklist

Use pin headers instead of soldering wires directly to the Arduino so you can swap parts easily. Transistor: 2N2222 or BS170 (for keying output)

Pushbutton switches (typically 5-10 for memories/functions).

A critical requirement for a schematic repack in the amateur radio context is RF filtering.