K3ng Keyer Schematic Repack

Don’t just copy the original pin_settings.h —the repack changes pin assignments to minimize trace crossings.

The necessity for a schematic repack stems from the evolution of the hobbyist workspace. The original project documentation provided a "menu" of hardware options: one diagram for the display, another for the paddle input, and disparate notes for PS2 keyboards or speed potentiometers. While comprehensive, this approach forced the builder to mentally splice circuits together before even heating a soldering iron. k3ng keyer schematic repack

| Mistake | Why It Happens | How the Repack Helps | | :--- | :--- | :--- | | | Dit and Dah pins swapped in code or wiring. | Repack shows physical orientation. | | Floating Inputs | No pull-up resistors on paddle lines. | Repack explicitly shows 10kΩ from pin to +5V. | | Key Output Always Active | MOSFET gate tied to 5V without current-limiting resistor. | Repack highlights the 220Ω series resistor. | | LCD Glitches | Missing I2C pull-ups on SDA/SCL. | Repack includes 4.7kΩ resistors on I2C lines. | Don’t just copy the original pin_settings

So, before you download the 7000-line .ino file and panic, find a repack. Print it out. Grab your Nano, a handful of resistors, and a MOSFET. And get ready to send your first perfect “CQ” — knowing that every dit and dah is guided by a schematic that finally makes sense. While comprehensive, this approach forced the builder to

Many failed builds trace back to noisy power. A good repack schematic includes: