Harris Intraplex HD Link RF, Руководство по установке и эксплуатации

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HD Link Installation & Operation Manual 2 – Functional Design
Version 2, April 2010
2-8 Harris Corporation
Intraplex Products
● Balanced input impedance of greater than 10 kOhms
● Balanced output impedance of less than 52 Ohms
● Adjustable audio input level range of b10 and +24 dBu
● Adjustable audio output level of between 0 and +16 dBu
Channels 1 and 2 have independent settings, and Channel 1 can be on while Channel 2 is off or vice
versa. While not suitable for high fidelity program audio, G.722 coding is ideal for high quality voice
talkback circuits and for transmission of voice-based programming such as talk shows or sports
coverage.
2.4.2 In-band Messaging and Synchronization
The HD Link STL system now offers in-band configuration of some receive parameters to save you a
trip to the tower site to configure your receiver. The transmitter uses a low-bit rate channel to send
this information to the receiver at a rate of once per second:
● Audio channel parameters
•
On or off
• Sampling rate
• Word length
• Stereo or mono mode
● Auxiliary audio channel state – On or off
● LAN port IP address for return path tunneling
On the receiver, you can select whether or not to use this Service Sync functionality. If you do use it,
the configuration parameters are locked on the receiver and passed from the transmitter; the
parameters cannot be changed on the receiver as long as the
Service Sync is enabled.
2.4.3 Redundancy
The HD Link system now supports transmitter and receiver redundancy with one transmitter or
receiver in Active state and the redundant transmitter or receiver in Standby state. For transmitters,
an external Main/Alt controller manages the redundancy state (Figure 2-3). Both transmitters are set
to Standalone and connected as shown.
HDLINK
A
HDLINK
B
Main/Alt
Controller
Ethernet
Switch
Other
Network
Elements
(e.g.
Exporter)
HD Port
HD Port
Control
Status
Status
Control
RF OUT- A
RF OUT- B
RF OUT- Ant
Figure 2-3. Transmitter Redundancy