III.
Features and Operation
The AES-403 Multi Switcher Audio System is designed to select one of two AES3 compatible
feeds or by DIP selection accept an analog L/R balanced input in place of the B digital input and
route it to up to two balanced digital outputs. It also contains a high quality digital to analog
converter providing a balanced left and right output. The unit features a front panel headphone
output and volume control for easy confidence monitoring. The AES-403 can be used as a totally
automatic switcher sensing loss of clock or any error displayed on the front panel to command the
switcher to select the alternate feed. In addition to digital error switching, the unit features a
silence sense circuit for switching upon audio failure conditions. All automatic switching functions
are user defined and can be initialized with a simple DIP switch setting upon installation of the
unit. Command of the switcher can also be performed manually at the front panel or remotely.
Remote control of the unit is accessed through the rear panel 9 pin D connector for simple
momentary closure or through the RS232/485 serial interfaces on the rear panel of the unit. For
simple momentary ground closure to the appropriate pin selects channels and error reset. Status
of channel selected and error flag is also available at this connector. Refer to the connection table
3 for connection information. The interface is compatible with open collector command. The AES-
403 su5 V.D.C. for powering open collector actuators. An optional delay is provided to
prevent the unit from switching on momentary interruptions that can occur in external equipment.
Through application of a DIP switch the unit can either switch immediately upon detection of
digital errors or wait 5 seconds and then switch. This delay prevents the unit from switching under
transient conditions.
IV.
Initial Operating Set up
Attach input and output connections to the unit using the appropriate connector. Plug the remote
control plug in and tighten the connector screws in place. You may select any or all of the error
flag and/or silence sense switching which will command the switcher to switch to the alternate
path. Refer to
AES-403 DIP Switch Programming Guide of Operation
on page 5 for switch
options. Refer to the factory default section of the table for supplied switch conditions. If the
default conditions are satisfactory for your intended use no further changes need to be made. In
order to change the DIP SW 1, 2 settings remove the front panel by removing 1 - #4-40 Phillips
head screw in of the top cover located in the front center of the cover and 4 - #6-32 front panel
screws. The front panel can now be removed and the DIP switches located which are on the front
panel PC board. Other error flags and the silence sense error are selected by placing the
designated DIP switches to the on position. Once DIP switch positions are selected the unit is
ready to be powered up for operation. When the silence sense error is selected for switching,
there are several configurations possible. It is possible to monitor both left and right channels and
switch upon complete audio loss or to have the silence sensor switch upon loss of left or right
channel individually. This feature was added so that non correlated audio feeds can cause the
silence sensor to switch where one feed may take precedence over another. Selection of L+R,
Left, or Right only audio is done by DIP SW S1 selection.
4