Overview
The Phoenix A8920A audio module is capable of inputting and outputting up to 4 audio
channels. The audio module occupies one audio slot (color coded black) and with up to
four slots available, each node has a capacity of 16 channels. The audio interface
connector is four, ganged RJ45 connectors located on each card. The audio module
supports an audio test pattern, similar to GE Security standards.
Tools and materials required
The audio modules are held in place with simple thumbscrews with screwdriver slots.
The only tool recommended is a small flat blade screwdriver.
Installation instructions:
1. Configure audio module:
Prior to installation, the audio modules need to be configured for proper
use in the system. Refer to the Fig. 1 and Fig. 2 for switch locations and settings.
a. Input termination:
Input termination should be set depending on your system
requirements. You can choose either high-impedance (default) or 600 ohm
termination on an individual channel basis.
b. Input range:
Based on the level of input signal you will be applying the
specific channel, you may choose to modify the input range selection switches.
By default, the switches are set to high range (+18dBu) and will transmit any
audio signal within the specifications of the unit. If lower level input signals are
expected, you may change the input range to low (+8dBu) to increase the overall
signal to noise ratio. Clipping (distortion) however, will occur if input levels exceed
+8dBu. Note that for each channel, two switches must be thrown to change
the input range.
c. Output range:
To normalize the system, you must switch the output range
switch to the same setting as the CORRESPONDING input range switch. Note, this
does not mean that the switches on the same board need to be the same, just
that the switches at the input node, must match the switches at the output node.
If multiple outputs are mapped (broadcast mode) than all outputs must be set to
the same gain range.
AUDIO OUTPUT
RANGE
AUDIO INPUT
TERMINATION
Figure 1. Audio Level Switch Locations
AUDIO INPUT
RANGE
Installing the Audio Module
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