Intercom Amplifier The ST-IC1 is the ideal choice where an intercom system is to be installed, or where an amplifier is needed to bring a mic level up to a 1 W speaker level with optional muting capability. The ST-IC1 has one input, one output and two muting control terminals. The input accepts a dynamic mic, a condenser mic (a phantom supply input terminal is provided to power condenser mics), an 8 Ω speaker or a 45 Ω speaker. The gain range of the module is sufficient to accommodate this wide variety of source levels. The output is ground-referenced, and drives more than 1 watt RMS into an 8 Ω load. The output circuit can be connected to any load impedance of 4 Ω or greater. Features: Intercom Electronics Intercom with Push-to-Talk Mic or Speaker Input 8 Ω or 45 Ω Speakers Bidirectional Communication Option Specifications: Frequency Response:300 Hz to 4 kHz (+/- 2 dB, filtered for voice band intelligibility) Gain:Off to 70 dB (adjustable) Input level for 1 W RMS output:-60 dBu (8 Ω source); -55 dBu (600 Ω source) THD+N:< 1% (1 kHz, referred to 1 W @ 50 dB gain) Residual Noise (below 1 W):< 75 dB (60 dB gain setting, unmuted) Operating Output Power:1 W RMS Maximum Output Power:1.5 W RMS (before clipping) Mute Attenuation:> 115 dB (1 kHz) Mute Switching Type:Solid-State, no relay contacts used Mute Release Delay:15 ms Power Requirement:GROUND-REFERENCED, 24 Vdc @ 175 mA Ambient Operating Environment:0 C to 50 C
