Raytheon SNV-12, Инструкция по установке и эксплуатации

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SNV-12 Operations Manual
4-6
4.6 Site Voter (SVM) Module
4.6.1 Features and Functions

Accepts Audio From The Receiver

Measures Various Parameters Of Incoming Signal

Provides Delay To RX Audio If Selected

Transmit Audio Output

Internal RX/TX Audio Level Adjustments

Audio Level Indicators And Measurement Points
4.6.2 General
The Site Voter Module interfaces with a receiver and measures its Noise Level or SNR, which
it reports to the CPM-3 module as a Signal Quality Number. The SVM's front panel contains
the following controls and indicators (detailed descriptions later in text):

TX SEL LED (yellow); lit when this site is selected for transit by the TX Steering
function.

SELECT/NORM/DISABLE; toggle switch selects one of the three states.

VOTED LED (green); lit when this site is voted best.

UNSQ LED (yellow); lit when the site is receiving a valid (voting) signal.
Also flashes to indicate that the module is in the Select Mode.

TX LED (yellow); lit when this site's TX audio and TX control are enabled.

FAULT LED (red); lit if this module has faulted. The SVM Fault LED will also be
illuminated if a line fault is detected for the associated site. The SVM-2 will flash this
LED when the module is in the Disable Mode.

RX INPUT AUDIO adjustment potentiometer and level indication test point & LEDs
The SVM Module provides parallel status signals and inputs to interface with an external
console. These I/O pins are protected from damage by high voltage transients.
When the voting system is first installed, the installer using the audio level test point & LEDs
to set the proper internal input audio level of each SVM Module.
The SNV-12 SVM Modules are interfaced to a backplane voted audio bus that carries the
currently voted signal to the Console Interface Module. A transmit audio bus feeds each SVM
Module from the Console Interface Module. Transmit and receive audio are extended to
additional SNV-12s when site expansion (past 12 SVMs) is required.
The SNV-12 votes audio, no matter what its source. The site receiver link to the SVM
Modules may be leased lines, hard wire, or E&M pairs.
4.6.3 Hardware Description
The SVM-2 Module contains a Texas Instruments TMS320C5409 DSP with 32K words of
internal RAM, and 128K words of non-volatile flash memory. A 14-bit Analog-to-
Digital/Digital-to-Analog converter provides an analog interface. The module also contains
various parallel I/O for reading control inputs, maintaining control outputs, and controlling the
various audio gates. The SVM communicates with the CPM Module by using its MCBSP high-
speed synchronous serial port.