Clear-Com SB-704 is a 4-Channel Switchboard Main Station - 5-channel X 10 station assignment matrix, no speaker - with built-in 2-amp power supply, rack mount (2RU).
SB-704 includes all of the features of the MS-704, with a 4 x10 assignment matrix in place of the internal speaker (external speaker required for station monitoring). The station features a ten-position slide switch matrix that allows assignment of any of the ten intercom lines to any of the four intercom channels, to an isolated separate party-line, or to an off position.
Spécifications
Panel Microphone Input
Input Type: Electret
Input Impedance: >=2K
Mic Limiter Threshold: 0dBu ±3dB
Mic Limiter Range (SB-704): >= 15dB
Headset Microphone Input
Input Type: Dynamic
Input Impedance: >= 1K
Mic Limiter Threshold: 0dBu ±3dB
Mic Limiter Range (SB-704): >= 15dB
Program Line Input
Maximum Level before Clipping: >= 20dBu
Input Impedance: >= 5K
Headset Output
Load Impedance: >= 8
Output Impedance: <= 25
Output Limiter Threshold: +5dBu ± 3dB
Maximum Output Level before Distortion: >= 17dBu
Speaker Output
Load Impedance: >= 4
Max Output Level before 1% Distortion: 20dBu ± 2dBu
Party-line Output
Off Noise: < -74dBu
Output Impedance: >10K
Party-line Input
Crosstalk: < -60dB
Max level before Clipping: >= 12dBu
Sidetone Null Capability: > 25dB
Stage Announce/Balanced Line Out
Type: Balanced
Output Impedance: >= 200
Load Impedance: >= 600
IFB/Hot Mic
Type: Unbalanced
Output Impedance: 150
Load Impedance: >= 600
Frequency Response
Panel Mic - Party-line: 600 - 10KHz ± 3dB
Headset Mic - Party-line: 200 - 12KHz ± 3dB
Headset Mic - Line Out: 200 - 12KHz ± 3dB
Program Input - Party-line: 100 - 17KHz ± 3dB
Program Input - Headset Out: 200 - 10KHz ± 3dB
Program Input - Speaker Out: 300 - 10KHz ± 3dB
Party-line - Headset Out: 200 - 10KHz ± 3dB
Party-line - Speaker Out: 300 - 10KHz ± 3dB
Max Distortion
Panel Mic - Party-line: <= 0.5%
Headset Mic - Party-line: <= 0.5%
Headset Mic - Line Out: <= 0.5%
Program Input - Party-line: <= 0.2%
Program Input - Headset Out: <= 0.2%
Program Input - Speaker Out: <= 0.5%
Party-line - Headset Out: <= 0.2%
Party-line - Speaker Out: <= 0.5%
Noise
Panel Mic - Party-line: < -65dBu
Headset Mic - Party-line: < -70dBu
Headset Mic - Line Out: < -55dBu
Program Input - Party-line: < -85dBu
Program Input - Headset Out: < -60dBu
Program Input - Speaker Out: < -60dBu
Party-line - Headset Out: < -50dBu
Party-line - Speaker Out: < -50dBu
Max Gain
Panel Mic - Party-line: >= 37dB
Headset Mic - Party-line: 41dB ± 2dB
Headset Mic - Hot Mic Out: 55dB ± 3dB
Headset Mic - Announce Out: 55dB ± 3dB
Program Input - Party-line: >= -16dB
Program Input - Headset Out: >= 18dB
Program Input - Speaker Out: >= 24dB
Party-line - Headset Out: >= 34dB
Party-line - Speaker Out: >= 40dB
Min Gain
Panel Mic - Party-line: <= 25dB
Mains Power
Input Voltage Range: 100 - 240 VAC
Input Frequency Range: 50 - 60 Hz
Input Power: <= 60 VAC
Output Voltage: 30 VDC ± 0.5V
Output Current per Channel (Continuous): 1.2 A
Output Current per Channel (Peak): 2 A (Do not exceed the 1.2A rating for more than 2 seconds per 1 minute period)
Short Circuit Recovery Time (1st short): <= 0.5 sec
Short Circuit Recovery Time >= 20 shorts in 20sec): <= 20 sec
Station Capacity
Up to 40 RS-601 beltpacks or 10 speaker stations or 12 headset stations distributed over all channels
Rear Panel Connectors
Switched Intercom: (10) XLR-3M (1 per channel)
Intercom: (4) XLR-3M (1 per channel)
Announce Out (1) XLR-3M (audio)
Program In: (1) XLR-3F
Hot Mic / IFB Interface: (1) 1/4 in. (0.64 cm) phone jack
External Speaker: (1) 1/4 in. (0.64 cm) phone jack
Accessory: (1) DB-15F
AC Power: IEC 320 connector
Rear Panel Controls
(1) Power switch
(4) Intercom On/Off Switches
Front Panel Connectors
Panel Mic: (1) 1/4 in. (0.64 cm) panel mounting jack