Motorola APX 7500, Подробное руководство по обслуживанию

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September 9, 2011 68009482001
4-24 Feature Operation: Crossmute Operation (L999_ required)
NOTE: Refer to the external equipment’s manual to ensure its maximum input audio specification is
not exceeded.
The connection is a dedicated 3.5 mm audio jack provided at the rear panel low speed connector
board of the Consolette and labeled P100. A three-conductor 3.5 mm TRS (tip, ring, sleeve)
connector or stereo plug should be used in conjunction with this jack. P100-1 accesses the sleeve
(ground) of the plug, P100-2 accesses the tip (left speaker), and P100-3 accesses the ring (right
speaker). The Consolette does not provide a true stereo output at this jack; however, the same
receive audio and alert tones are supplied to both the right and left speaker connections.
NOTE: Connecting a two-conductor plug of the same size into this three-conductor jack will ground
the ring (right speaker) and subsequently the tip (left speaker) since their audio is from the
same source. This will result in no audio being heard.
4.25 Crossmute Operation (L999_ required)
The Consolette supports a Crossmute Interface on the DB25 connector on the rear panel.
Crossmute allows an automated method of muting a Consolette while a second Consolette in close
proximity is transmitting. This prevents noise due to RF desense from being heard on the speakers
of the nearby, non-transmitting units.
Signals include:
• MUTE_IN* – This is a logic input to cause the Consolette to mute the Front and External
speakers as well as all the other Rear Panel audio sources (PA, Recorder, etc). The Consolette
will mute when this input is pulled to less than 0.8VDC to ground.
• TX_ACTIVITY* – This is an active low logic output that indicates when the Consolette is
transmitting. When transmitting, this output is driven to ground.
• GND
The TX_ACTIVITY* output of one Consolette can be connected to the MUTE_IN* input of another
Consolette and vice versa. The Crossmute hardware is designed such that the TX_ACTIVITY*
output from one Consolette is the correct level to drive the MUTE_IN* input on another. When
Crossmute is enabled on the Consolette and it is transmitting, the Consolette will assert its
TX_ACTIVITY* output pin. This output will then activate the MUTE_IN* input of the connected
Consolette causing the Consolette to mute the Front and External speakers as well as all the other
Rear Panel audio sources (PA, Recorder, etc). When the MUTE_IN signal* is asserted, the Speaker
Mute icon will show on the auxiliary display. Refer to
section 4.9 for additional information regarding
the interactions between MUTE_IN*, the Speaker Mute Button, and the Headset(s).
4.25.1 Connection
The Consolette comes equipped with the Crossmute functionality. To operate the feature, first
connect a cable between two APX Consolettes via the DB25 connector on each rear panel. The
MUTE_IN* input is accessible on the DB25 Accessories Connector (J104 pin 16). The
TX_ACTIVITY* output is accessible on the DB25 Accessories Connector (J104 pin 1).
Cables are not provided by Motorola, refer to Chapter 6 “Cabling Diagrams and Rear Panel” .
When the Crossmute cable is connected, the Crossmute feature will function automatically. To
disable the Crossmute functionality, disconnect the cable.