audio intercom with internal power supply
audio intercom Audio door phone for special design 1) Direct calling and dual talking 2)Unlock function
audio intercom
Single house door phone applicable to conveniently identify a visitor150 meters effective wiring with 0.8 mm cooper wireCall sound output power is high 300mW across 8 ohms, and low 50mW across 80 ohms
audio intercom with internal power supply
