Raytheon SNV-12, Инструкция по установке и эксплуатации

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SNV-12 Operations Manual
1-2
1.2.4 Console Interface Module
The Console Interface Module is the interface between the voting system and a dispatcher‟s
audio console; it takes in console audio for transmission and supplies the voted audio signal. To
facilitate setup and troubleshooting, the CIM‟s front panel speaker can be set to monitor either
voted audio or a combination of console transmit input audio and voted output audio. All
transmit audio is processed in this module, and then routed onto the backplane‟s TX Audio Bus
to be picked off by SVMs as directed by the CPM. The CIM can be set to detect EIA
sequences in the incoming Console TX audio to be used for transmitter keying, and to
condition audio output to transmitters by adding keying tones. Variable digital audio delay
allows console transmit audio signals to be delayed to prevent loss of first syllables until all
system keying delays (including slow-to-key repeaters) are past.
1.2.5 Control Processor Module
The SNV-12's Control Processor Module controls the entire voter via an internal high-speed
serial bus; it requests and receives Signal Quality or SNR, Noise Level, COR Presence
(receiver squelched/unsquelched state) and Speech Present information from each Site Voter
Module. PTT inputs are presented on an interrupt basis (rather than by the module polling
process) for quick response. This information is used to make decisions that involve voting and
transmit steering, etc. The CPM also provides an RS-232 serial port that allows programming
and monitoring of all SNV-12 functions via an external computer or serially interfaced console.
The CPM-3 adds an Ethernet port for in-system programming and an enhanced web browser-
based user interface for controlling and monitoring the SNV-12 system. The front panel of the
CPM Module contains a Fault LED, along with three other LEDs that indicate the unit's status
in an expanded system, labeled: Master, Expansion 1 Expansion 2. In expanded systems, up to
three SNV-12 chassis may be connected together to create a voting system of up to 36 sites.
The CPM-3 has an additional LED on the front panel, labeled LINK, to indicate network link
status.
1.2.6 Site Voter Module
The SNV-12 may house as many as 12 Site Voter Modules. Each of these modules interface
with an external radio receiver (and/or transmitter) and measures the Noise and Signal levels of
its receive audio. The signal-quality information is passed on to the CPM module for use as the
basis for voting. Other features and functions of this module include speech detection (for line
fault determination), adjustable RX audio delay, and transmit audio output. Front panel
switches allow any site to be eliminated from voting or to be "Selected" as a voted site
regardless of its signal quality. Front panel LEDs indicate if the associated site is disabled,
voted, or selected for receive or transmit. Other LEDs indicate if the site's receiver is
unsquelched, when TX audio is being steered through this module to a transmitter at the
associated site, and if the module (or site) is experiencing a fault condition.
System transmitters should be connected to this module (rather than the CIM) as only the SVM
TX outputs have the special TX audio features such as keying tones, hangtime, TX audio delay,
etc. The SVM module takes TX audio from the TX Audio bus on the voter backplane and
routes it through a gain stage and 600 ohm transformer on its way to the rear panel terminal
block. No processing of TX audio occurs on the SVM; this is all done on the CIM Module.