Handset Transducer

A handset transducer is a component used in enterprise-grade VoIP desk phone handsets. It performs two-way conversion between electrical signals and audible sound. In its speaker function, it converts incoming electrical audio signals into sound waves that the user can hear. In its microphone function, it converts the user's voice (sound waves) into electrical signals that are transmitted to the phone system. This enables full-duplex voice communication through the handset. The transducer typically consists of a diaphragm, a magnet assembly, and a coil or piezoelectric element, all housed in a plastic casing. It is designed to fit within the handset earpiece and mouthpiece sections. The transducer operates on electromagnetic induction or piezoelectric principles. For the speaker, electrical signals create varying magnetic fields that move the diaphragm, producing sound. For the microphone, sound waves vibrate the diaphragm, generating corresponding electrical signals. Key parameters include rated impedance (150 Ω ±15% at 1 kHz per IEC 60118), sensitivity (-45 dBV/Pa ±3 at 1 kHz per IEC 60318-4), frequency range (300–3400 Hz per ITU-T P.310), rated power (0.5 W maximum continuous), operating temperature (-20 to 60 °C non-condensing per IEC 60068-2-1/2), storage temperature (-40 to 85 °C per IEC 60068-2-1/2), humidity (5–95% RH non-condensing per IEC 60068-2-78), ingress protection (IP54–IP65 per IEC 60529), weight (5–15 g without cable), dimensions (10–20 mm diameter), cable length (1.2–2.5 m, coiled or straight), and connector type (RJ9/RJ10 per IEC 60603-7). These values are directory reference ranges; actual specifications must be confirmed with the legal manufacturer or supplier for the specific model. The transducer is a component, not a standalone product, and is selected based on handset design requirements. It is not a certified end product; standards listed are for verification and procurement reference only.

The handset transducer uses electromagnetic induction or piezoelectric effects. In speaker mode, an electrical audio signal passes through a coil, generating a varying magnetic field that interacts with a permanent magnet, causing a diaphragm to vibrate and produce sound waves. In microphone mode, incoming sound waves strike the diaphragm, causing it to vibrate; this movement either moves a coil within a magnetic field (dynamic) or stresses a piezoelectric element, generating a corresponding electrical signal. The transducer is designed to operate within the telephone band (300–3400 Hz) and is optimized for voice clarity.