Clear-Com ICS-21, Instruction Manual

I C S - 2 1 / 2 1 D T   S P E A K E R   S T A T I O N

1 - 1

OPERATION

DESCRIPTION

The Clear-Com ICS-21/21DT speaker station is designed for use in theatres, live 
performances, industrial environments, and small television facilities. It features 
excellent speech intelligibility, even in high noise levels, and can be customized 
through its programmable options.

The talk button operates in momentary mode. The integral microphone and 
speaker offer half-duplex communication. The ICS-21/21DT offers both visible 
and audible call signaling to attract the attention of operators.

A balanced program input allows the monitoring of external audio through the 
speaker. This program input can also be used as a paging function.

The integral speaker’s volume level can be adjusted using a front-panel knob. An 
internal control allows setting a minimum speaker level. An automatic speaker 
switching circuit will quiet the speaker when the talk button is activated.

The ICS-21/21DT is powered locally. In permanent wall installations, a 16-VAC 
doorbell transformer will provide a convenient source of power. In DT-Box 
installations, a 14- to 18-VAC wall-mounted transformer will suffice. The 
connections to this transformer are made to the circuit board’s two-terminal, 
plug-on connector. The unit mounts either in a standard four-gang electrical 
outlet box or in an optional Clear-Com DT-Box. The extra-thick front panel and 
compact, surface-mounted circuitry results in a reduced size and lighter weight 
package that maintains Clear-Com ruggedness. The Matrix frame connects to an 
eight-wire modular jack.

OPERATION

Normal operation of the ICS-21/21DT speaker station only requires access to 
the front-panel controls. The controls located elsewhere on the unit are intended 
to be set-and-forget in nature. For intercom operation, set the intercom-level 
control to the desired level and press the talk button when talking.

FRONT PANEL

The controls, indicators, and connectors on the ICS-21/21DT front panel are 
shown in Figure 1 on page 1-2 and are described in the text that follows. 

Talk Button and Light

This momentary-action button activates the panel microphone so that audio is 
transmitted to the answer-back label or the programmed station/interface talk 
label. This light must be on for audio to be transmitted. It lights when the talk 
button is held.

• The ICS-21/21DT offers 

simple operation. 

• Fully operational from the 

front panel.

• Features include a talk 

button, answer-back 

facility, and program-level 

control.

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