64-character standard ASCII character set in accordance with ANSI INCITS 154.
2.3
COMMAND GENERATOR
Command generator shall accept commands from the control panel and generate
the control signals necessary to operate radio switches over the radio
channel. The generator shall contain a digital tone synthesizer,and
station control over communication links to the transmitter.
2.4
TRANSMITTER
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NOTE: Director of Information Management
coordination must be achieved and appropriate
frequency assignment granted by the installation.
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A continuous duty VHF transmitter shall be provided to transmit at a
The conducted spurious harmonic emissions shall be less than minus 75 dB.
Frequency stability shall be a maximum of 0.0005 percent over the operating
temperature range. Modulation deviation shall be adjustable to plus or
minus 5 KHz. FM hum and noise shall be less than minus 60 dB. The
transmitter shall be designed to maintain a minimum field strength of 30
microvolts per meter at any point in the coverage area during transmission.
The Contractor has the option of using remote signal repeaters to ensure
sufficient field strength to control all radio switches. When multiple
transmitters are used to control radio switches of a particular group,
circuitry shall be incorporated to compensate for the transmission delay
over the communication links to the remote transmitter. A redundant
transmitter shall be provided to assume the functions of the primary
transmitter in the event of transmitter failure. Circuitry shall be
provided to detect transmitter failure and automatically switch over to the
redundant transmitter.
2.5
ANTENNA SYSTEM
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NOTE: The designer must show the topography on the
drawings.
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Antenna system shall utilize vertical polarization antennas, communication
links between transmitters and antennas, and matching networks as needed
for the proper coverage. Antenna shall be either omni-directional or
shaped coverage as determined by the Contractor from the topography. The
antennas shall be capable of withstanding the environmental conditions of
[201.2] [_____] km/hour [125] [_____] mph wind and [13] [_____] mm [1/2]
[_____] inch radial ice without failure. The antenna system shall be
selected by the Contractor to meet the requirements as determined from the
topography. Lightning protection shall comply with NFPA 780.
2.5.1
Grounding Conductor
Antenna grounding conductors shall be minimum 32-strand, No. 17 AWG copper.
2.5.2
Ground Rods
Ground rods shall be as specified in Section 16402 INTERIOR DISTRIBUTION
SECTION 16790A
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