§ Built-in AGC gain audio circuit § imported ICs, coupling capacitance § 2mm pinhole design § Japan's imports of gold-plated capacitor microphone § Dynamic closed-loop noise reduction circuit
10 to 80 m2 Impedance 600 ohms Frequency 20 ~ 20Khz Power 9 ~ 12VDC Size Φ15 * 50mm For HaiKang, Dahua DVR device |