K3ng Keyer Schematic Jun 2026

The authoritative source is the ( github.com/k3ng/k3ng_keyer ). Look in:

D9 (Sidetone) ---[1k]---(+) Piezo (-)--- GND k3ng keyer schematic

The built-in speaker pin (Pin 8) is weak. The schematic can be extended to include an LM386 audio amplifier circuit. This adds a 10k pot for volume and a small speaker. Look for "K3NG Audio Filter" schematics. The authoritative source is the ( github

Safely interface Arduino’s 5V logic to the transceiver’s key input (which may be 0–12V, high impedance, or require current sinking). or require current sinking).