K3ng Keyer Schematic -

The biggest mistake new builders make is connecting Pin 9 (Key Out) directly to their radio's "CW Key" jack.

"Look here," Silas pointed a calloused finger at the screen. "The schematic is designed around an Arduino, usually a Nano or a Mega. But see this section? It handles the paddle inputs. And this? The PTT (Push-To-Talk) output. It’s isolated. You won't fry your radio." k3ng keyer schematic