Circuit Diagram
How to Build It
- Build an audio oscillator using a BC547 transistor, a coil/capacitor or an RC network, to generate a continuous tone.
- Connect the oscillator's output to a small speaker.
- Add a push button (a telegraph key) in series with the circuit's power supply.
- Power the circuit.
- Press and release the button in Morse rhythm — the tone should sound only while the button is held.
Bill of Materials
| Product | Code | Qty |
|---|---|---|
| Inductor | MCQ1V1608-R470-R | 1 |
| Actuation push button | H570033 | 1 |
| Speaker cable | KAB0352 | 1 |
| Capacitor (electrolytic/ceramic/SMD/film) | #N/A | 1 |
| Transistor (incl. IGBT) | — | 1 |