Spectracom 8194B, Инструкция по эксплуатации

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8194B, 8195B, 8197B Spectracom Corporation
GPS Ageless Master Oscillator Instruction Manual 2-10
2.7 Initial Operation
After completing antenna and power connections, switch on the power. Observe that
the front panel POWER lamp turns on. The Major and Minor Alarm lamps are also
turned on during initial operation. The receiver will now acquire and lock to GPS
satellites currently in view of the antenna. The TRACKING GPS lamp turns on and the
Minor Alarm lamp turns off when the receiver acquires a minimum of four satellites and
has achieved a 3-D fix for one minute. This typically takes less than 20 minutes to
accomplish during initial installation. Once the receiver has a 3-D fix in its new location,
the position information is loaded into non-volatile RAM. Having current position
information greatly reduces the time to first fix on subsequent power cycles to less than
one minute, or less than 10 seconds if a backup power source is present.
Models 8194B and 8195B require a minimum of 4 hours to reach operational
temperature and stabilize and discipline to GPS. The Model 8197B may require up to 6
hours. The OSC LOCK lamp turns on and the Major Alarm lamp turns off when the
oscillator is disciplined to the GPS reference. The unit will now operate in accordance
with the specifications listed in this manual.
2.8 Qualifying the Installation
Typically, the front panel Tracking GPS lamp illuminates within 20 minutes of turn on.
This lamp indicates that receiver is tracking at least 4 qualified satellites and a 3-D
position fix has been obtained. If the Tracking GPS lamp does not turn on, a cable or
reception problem may exist. Refer to Section 2.9 for troubleshooting assistance.
Reception quality can be evaluated using the performance and status logs provided by
the receiver. Commands to retrieve operational information are issued through the front
panel RS-232 Com port. To communicate with the receiver, a terminal or computer with
terminal emulation software (i.e. ProComm Plus, Hyper-Terminal, etc.) is required.
Configure the terminal for ANSI emulation, 9600 baud and a character structure of 1
start, 8 data, and 1 stop with no parity. Flow control is not required, though xon / xoff is
supported.