US Utah-400, Настройка и эксплуатация, Страница: 101 / 157

144x144 Router
4-35
Deluxe Output Board
Addition of dither to output signals at user discretion.
These capabilities are accessed by control and status monitoring via embedded JTAG control
structures included in the Utah-400 router platform.
Further, these operations are performed in concert with the channel status (C-bit) indications
at the inputs, and the channel status outputs are set appropriately, according to parameters
from inputs and commanded functions.
This module also includes the provisions present on the standard output module (USI 121027-
1), i.e. signal presence detection, protection input switching capability, and monitor matrix
functionality.
In order to properly perform its intended function, the V-fade facility is expected to operate on
signal sources that are synchronous to the router’s DARS (digital audio reference signal). If
either (or both) the pre- or post-switch sources are asynchronous, the hardware will still exe-
cute the commanded V-fade operation, but at the switching point, it will have to acquire the fre-
quency and phase of the new signal, outputting an improper discontinuous AES signal while it
does so. Since there can be no possible guarantees of the responses of downstream equip-
ment, this mode of operation is not recommended and should be avoided.
All other signal manipulations are suitable for both synchronous and asynchronous AES
sources.
This module is substituted for the standard output module in a Utah-400 chassis, on an as-
needed basis; to bring these enhanced features to those specific system outputs.