Passive Buzzer — 9042 Piezo Element for PWM Tone Generation (5-Pack)

A genuine passive piezo buzzer (model 9042) with no internal driver circuit. Unlike the catalog's Active Buzzer Module — which plays one fixed tone as soon as it's driven high — this passive buzzer only makes sound when it's fed an oscillating signal, making it the right part for lessons that generate actual musical tones and melodies with ledcWriteTone() or similar PWM tone functions.

Highlights

• Genuine passive piezo element — no internal oscillator circuit
• 16Ω impedance
• Rated for 3V / 3.3V AC drive signal
• Compact 9 x 4.2mm size
• Sold in a 5-piece pack

Typical Uses

Playing actual notes/melodies via PWM tone generation, alarms with variable pitch, and any lesson specifically teaching the difference between active (fixed-tone) and passive (frequency-driven) buzzers.

Compatibility

Works with any microcontroller PWM/tone output (e.g. ESP32 ledcWriteTone(), Arduino tone()). Requires an oscillating signal to produce sound — driving it with a plain digital HIGH/LOW like an active buzzer will not produce a tone.

What's Included

5x 9042 passive piezo buzzers.

Notes

This is a passive buzzer, not the catalog's Active Buzzer Module — the two are not interchangeable for a fixed-tone circuit driven by a simple digital write. Use a PWM/tone function to drive this part.