Symmetricom Z3801A, User Manual

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Chapter 1 Getting Started
Using Commands to Control Key Functions (Examples)
1-16 User Guide
Set the Receiver to exclude satellites which appear below a
specified elevation angle.
At the factory, and whenever the Receiver is preset, the Receiver is set
to seek satellites visible from zenith down to 10 degrees above the
horizon—down to an “elevation mask angle” of 10 degrees. The factory
elevation mask angle setting is intended to provide a full view of the
sky. The Receiver can be custom-configured to use a different elevation
mask angle.
Set the Receiver elevation mask angle using the command:
:PTIME:GPSYSTEM:EMANGLE <degrees>
Set the Receiver to display local time rather than
UTC time.
Set the offset from UTC time to local time using the command:
:PTIME:TZONE <hours>, <minutes>
To Install With a Limited View of the Sky, To Bypass
Position Survey Operation
In order to reach steady-state operation, the Receiver must know the
position of the antenna. The Receiver is able to collect enough
information from four satellites to compute this position. The “position
survey operation” takes in data from the satellites, iterating until the
antenna position is known to the required precision. The Receiver will
automatically use its position survey operation on powerup and
:SYSTEM:PRESET .
Alternatively, if the antenna position is already known to seconds of
arc, and the Receiver cannot see enough satellites, you may manually
enter antenna position as shown in the following text.
NOTE
An incorrect value for the position will confuse the Receiver, and will
degrade the timing information accuracy or even prevent tracking any
satellites.
Set the Receiver antenna position using the command format shown
below (for clarity, an example is provided rather than a complex
description.):
:PTIM:GPS:POS N,37,19,32.5,W,121,59,51.2,40.12