Installation manual

The wiring of the headset is to be as follows:
Pin 1 --- Mic common
Pin 2 --- Mic hot
Pin 3 --- Headphone common
Pin 4 --- Headphone hot
The mic and headphone wiring in the headset cord must be individually shielded. Do not connect
Pins 1 and 3 together. Headset extension cords or headset "Y" cables are not recommended be-
cause they will increase crosstalk between channels.
Panel Mic Connector: Clear-Com recommends the GM-9 and GM-18 plug-in panel microphones
for use with all stations having a panel mic connector. The GM-9 is 9 inches long and the GM-18 is
18 inches long. The microphone is an electret type. The 1/4 inch phone jack on the microphone
mates with the Panel Mic receptacle on the front panel.
To install a GM-9 or GM-18 microphone, use the following steps:
1 Check the set screw in the mic mounting flange to make sure it is clear of the threads in
the bushing.
2 Screw the microphone into the bushing hand tight.
3 Set the set screw on top of the bushing to lock the microphone in place.
Hot Mic Out / IFB System: Some Main and Remote Stations have an interface to the External
Line In jack on Clear-Com's IFB System. This connection is a 1/4 inch phone jack on the rear
panel. It provides a 0 dBv output signal from the selected headset or panel microphone on the sta-
tion. It connects using a standard 2-wire and shield stereo 1/4 inch plug-to-plug cable such as the
Clear-Com P/N 73016501 (18 inch) or P/N 73016502 (5 foot). It allows the station's microphone to
be used to cue talent through the IFB System. A control signal sent into this connector from the IFB
System can optionally disconnect the station's microphone from the intercom line(s). The jack is
wired as follows:
Ring --- Ext. IFB Control Signal Input
Tip --- Hot Mic Audio Output
Sleeve --- Ground (Shield)
Stage Announce Output: Some Main and Remote Stations have a 3-pin XLR male connector on
the rear panel to feed into a studio PA. Pressing the Announce button on the front panel places the
audio from the selected headset or panel microphone on the rear panel connector. Optionally,
pressing the Announce button can also disconnect the selected headset or panel microphone from
the intercom line(s). This option is controlled by the Interrupt Announce option switch. Simultane-
ously, if the program audio feed to the Announce Output is enabled, it is interrupted by the an-
nouncement. Program audio feed to the Announce Output is selected by setting a jumper on the
Main board to the ON position. The pinout of the Announce Out connector is as follows:
Pin 1 --- Ground (Shield)
Pin 2 --- - Signal
Pin 3 --- + Signal
The audio output is balanced and transformer isolated. It has a 600 ohm impedance and a nominal
output level of 0 dBv. A shielded twisted pair cable should be used in the cable wired to this
connector.
Relay Out: On Main and Remote Stations with an Announce button, a dry set of relay contacts is
provided through a 1/4 inch jack or screw terminals on the rear panel. These contacts can activate
an external device such as a PA amplifier to another room. The contacts are rated for 2.0 Amps at
24 VDC. If screw terminals are provided on the Main Station, their connections are labeled N/C, C
and N/O. The 1/4 inch jack is wired as follows:
Clear-Com System Installation Manual
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