Overview

RTS' MCE-325 is a four-channel, programmable intercom station. It may be used as a headset station or, with the addition of the MCS-325 Modular Speaker, as a speaker station. It may be mounted in a console or equipment rack via optional mounting kits. The MCE-325 can be used with either two-wire or four-wire intercom lines, or a combination of both. In the labeling on the MCE-325, references to channels 1, 2, 3, and 4 indicate two-wire lines; references to four-wire A and four-wire B indicate four-wire lines.

Features

• Call signaling is accomplished using an inaudible (20 kHz) signal to activate a call indicator LED.
• Remote "talk-off": Active, unattended remote station microphones may be deactivated by momentarily injecting an inaudible (24 kHz) signal into the corresponding intercom line. The MCE-325 can send and receive “talk-off” signals.
• VOX circuit: The MCE-325 may be programmed for voice activation of the microphone.
• Simple IFB: Program audio assigned to a channel is interrupted during talk.
• External device keying: External devices, such as two-way radios, speaker mute relays, or paging systems may be activated through key outputs at the auxiliary connector on the rear panel. The key outputs may also be used to expand the simple IFB function, allowing any one of a number of MCE-325 stations to interrupt the program source and talk on the line.
• Microphone Limiter: The microphone preamplifier circuit contains a limiter, which helps to equalize voice levels.
• Fully programmable: Retains programming even when power is shut off.

Specifications

• Bridging Impedance (to line): 10,000 ohm typical
• Noise Contribution to 200 ohm Line: -90 dBu
• Call Signal Frequency: 20 kHz, crystal controlled
• Talk-off Frequency: 24 kHz, crystal controlled
• Microphone Preamplifier:
• Maximum Voltage Gain: 54 dB
• Frequency Response: 100 Hz to 8,000 Hz, ±3 dB
• Input Impedance: 1,000 ohms
• Limiter Range: 30 dB
• Headphone Amplifier:
• Maximum Voltage Gain: 30 dB
• Frequency Response: 100 Hz to 8,000 Hz, ±3 dB
• Headphone Impedance: 50 to 600 ohms
• Output Power 150 mW into 50 ohms
• Output Voltage Level 8 Vp-p
• Speaker Amplifier:
• Maximum Voltage Gain: 30 dB
• Frequency Response: 100 Hz to 8,000 Hz, ±3 dB
• Speaker Impedance: 8 to 16 ohm
• Output Power per Amplifier: 5W into 8 ohms
• Output Voltage Level: 16 Vp-p