GatesAir PT-353, Инструкция по установке и эксплуатации, Страница: 14 / 55

PT/PR-353 Program Audio Module Installation & Operation Manual 2 – Functional Description
Version 1.1
2-4 GatesAir
Intraplex Products
● TTL word clock signal
If the system detects an external timing source, a sample rate converter is enabled for the mode of
operation, and the EXT indicator light on the PR-353 module turns on. There is a priority scheme for
the input sources. If both the AES and word clock signals are used together, the system gives the
word clock priority, and the AES input is ignored.
2.9 Channel Status
2.9.1 Transport
The PT-353 and PR-353 modules transport AES channel status information from the source provided
at the PT-353 module to the output equipment that is driven by the PR-353 module. The modules
remove the channel status from the AES input stream arriving at the PT-353 module. Each channel in
the AES stream has its own channel status information, provided in 24 bytes. Therefore, channels A
and B together have 48 bytes of information per AES frame. In general, channels A and B contain the
same information, which means it is not necessary to transport the entire 48 bytes of information to
the PR-353 module. Therefore, only the non-zero data is transported from channel A and recreated
into channels A and B on the PR-353. (The Reed-Solomon forward error correction for both channels is
reconstituted at the PR-353 module.) If the channel A and B information is different, the full
information of up to 48 bytes is transported to the PR-353 module.
2.9.2 Overwriting
There are some situations in which the channel status data is overwritten on both the PT-353 and PR-
353 modules. On the PT-353 module, if the incoming channel status information indicates the data
word is over 16-bits in length, the channel status word length is overwritten to a 16-bit word length.
The PT-353 then dithers the word down to 16-bits for transport. On the PR-353 module, if an external
AES sync or word clock is engaged, the sample rate information in the channel status is overwritten to
reflect the external sync rate.
If the incoming AES channel status indicates the J.17 emphasis is turned on, this information passes
to the PR-353 module but the J.17 de-emphasis is not automatically turned on. The de-emphasis
feature must be engaged on by setting SW2/position 6 DOWN on the PR-353 module.
2.10 Web Browser Interface
IntraGuide Configuration and Management Software supports the PT/PR-353 modules. All customer-
configurable parameters and indicators are communicated to and from the interface. VU Meter and
gain control support for the interface are also provided.
2.11 Input/Output Connections
Two types of dual domain module adapters, MA-508/MA-509 and MA-558/MA-559, support the PT/PR-
353 module. These module adapters (MAs) provide analog and digital input and output, plus data and
alarm connections. The PT/PR-353 module can also be used with the existing MA-504, MA-505, MA-
510, and MA-511, with limited functionality. Appendix A gives more information on these MAs.