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2 CM-CU21 Rear Panel Controls & Connections
CM-CU21 Rear Panel Controls & Connections
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, Limiter, Test Tone and
Talkback Gang.
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.
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.
Fig 2-5: Rear Panel View Of CM-CU21
