Introduction
The AES-402 Digital Audio System comprises of a two input AES compatible switcher, four
output digital audio DA and digital to analog converter. The unit also has status and diagnostic
error indicators for troubleshooting. The AES-402 is intended for use at unattended transmitter
sites or for virtually any digital switching, distribution and/or D/A conversion application. The unit
has the capability to automatically switch inputs upon detection of loss of clock, digital error flags
and/or silence sense. In addition to these features, the unit can function as an interface standards
converter. As shipped from the factory the unit is supplied with XLR balanced connectors. For
unbalanced use such as the 75 ohm unbalanced AES standard for digital audio transmission
transformer adapters are available from Broadcast Devices, Inc. for conversion of the AES-402
I/O to unbalanced 75 ohm operation.
I.
Unpacking
Carefully inspect the unit after unpacking and make certain that no damage has occurred during
shipping. If damage is noted, contact the shipper immediately and file a claim for damages. Each
unit is carefully packed and carries full insurance against damage. Inspect the packing list and
make sure that the contents of the package match those described on the packing list.
II.
Installation and Connections
Select a space in suitable E.I.A. standard rack to locate the unit. Determine the local electrical
power supply voltage. As supplied from the factory, your AES-402 is setup for 100 – 240 V.A.C.
50 - 60 Hz. No external adjustment for local power standards is necessary if power available
conforms to the above rating. The AES-402 utilizes a switch mode power supply and
automatically adjusts for local power entry. Make connections to the unit following good
engineering practice. Supply power to the unit utilizing a three pronged grounded outlet. Do no lift
the electrical ground to the unit at the power receptacle as this will result in a safety hazard. In the
event of ground loops, lift the ground at the offending connection only. Make certain that the unit
is afforded proper ventilation in the area of the top cover vent.
A. Digital Interface
The AES-402 inputs are balanced XLR connections conforming to the AES standard. Each XLR
connection is terminated at 110 ohms as per the standard. The balanced digital outputs are also
XLR connections which provide 110-ohm transformer coupled source impedance as per the AES
standard. To unbalance any input or output unbalanced termination adapters can be purchased
from Broadcast Devices, Inc. Order P/N 75 – XLRM for inputs and P/N 75-XLRF for output
connections. All BDI adapters utilize BNC female interface for application to 75 ohm BNC
connectorized cabling.
B. Analog Interface
There is provided on the rear of the unit a left/right balanced analog output. This output is suitable
for driving 600-ohm balanced lines and is short circuit protected. A headphone jack and volume
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