PASCO PS-2175 GPS Position Sensor - Manual (Page 5)

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M o d e l N o . P S - 2 1 7 5 M o d e s
5
Modes
LED indicator lights in the GPS Position Sensor tell you whether or not the sensor is
ready to make measurements. If you see the green
DATA indicator, the sensor is ready.
If you see the red SEARCH indicator (or both green and red), the sensor is not ready.
At initial power on, the sensor enters initial search mode, in which it searches the sky
for available satellites. Initial search mode typically lasts between 30 seconds and 2
minutes. In initial search mode, the red
SEARCH indicator flashes.
When the sensor is actively tracking three or more satellites, it switches to GPS valid
mode. In this mode, the sensor continuously updates its position and velocity mea-
surements. In GPS valid mode, the green
DATA indicator glows steadily.
If the sensor cannot track at least three satellites, it enters GPS lost mode. In this mode
it continues to report its most recent position measurements. Use this “stale” data with
caution; it is incorrect if the sensor has moved since its last valid measurement. In
GPS lost mode, both indicators flash.
GPS POSITION
PS-2175
SENSOR
Point this surface
toward sky
DATA
SEARCH
ANTENNA
LED
Indicators
Initial search
mode
Tracking fewer than
three satellites
Tracking three or
more satellites
GPS valid
mode
GPS lost
mode
Tracking three or
more satellites
Table 1: Modes
Mode LED Indicators Reported Data
Satellite
count Note
Initial search
Data: off
Latitude: 0.0
Longitude: 0.0
0 No position available
Search: flashing (red)
GPS valid
Data: on (green)
Latitude: valid
Longitude: valid
≥ 3 Good positions available
Search: off
GPS lost
Data: flashing (green)
Latitude: last valid report
Longitude: last valid report
0
Stale positions available,
use with caution
Search: flashing (red)