Sonifex CM-CU21, User Handbook Manual

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CM-CU21 Commentator Unit User Handbook
7
CM-CU21 COMMENTATOR UNIT
REAR P
ANEL C
ONTR
OLS & C
ONNEC
TIONS
4
4 Rear Panel Controls & Connections
Fig 3-2: Rear Panel View Of CM-CU21
The rear panel of the Commentator Unit carries the four return audio inputs and all comm.,
talkback and mix output connectors. Four additional controls are located on the rear panel;
On Air Lock, Talkback Gang, Limiter and Test Tone.
On Air Lock Controls
The on air lock prevents any of the commentators on air buttons from being deactivated
accidentally. When the on air lock is enabled, an on air channel can only be deactivated by
first pressing the pushbutton located next to the on air lock switch. A slot in the rear panel
makes locating the on air lock pushbutton easy; simply position your finger in the slot in
the rear panel, indicated by the “ON AIR LOCK” text on the top panel, then slide your finger
down the slot until you reach the pushbutton.
Talkback Gang Switch
The talkback gang switch links the operation of each of the main commentators’ talkback
A and B buttons. When this switch is on, pressing one of the talkback buttons will
automatically activate the commentators’ other talkback button.
Limiter Controls
The limiter enable switch and level potentiometer control the limiter that is applied to the
main mix outputs. The potentiometer sets the threshold level at which the limiter becomes
active, and has a range of between -13dB to the maximum output level of +25dB.
Test Tone Switch
The Commentator Unit has a built in Test Tone generator which selectively routes a line-up
tone to all outputs to assist channel identification and cabling checks. There are two test
tone modes; manual and auto. Regardless of mode, a 1 kHz tone is permanently routed to
the mix outputs and the PPM meter will indicate that the signal level is 0dBu. The test tone
is enabled by sliding the switch to the upper “ON” position. To change the test tone mode;
keep the Commentator 1 and Commentator 2 On Air buttons pressed for 2.5 seconds.
With the test tone in manual mode, all On Air and Talkback buttons will flash amber. The
test tone can be routed to the Comm and Talkback outputs by pressing the corresponding