Orolia Ltd PLB-4 User Manual
14
20 minutes. The inclusion of GPS based positional information can greatly reduce the
time it takes for the SAR authorities to arrive on scene. When speed of response and
accuracy of location are important considerations, then GPS PLBs offer the best in
performance.
time it takes for the SAR authorities to arrive on scene. When speed of response and
accuracy of location are important considerations, then GPS PLBs offer the best in
performance.
The location of a GPS PLB can be determine to a typical positional accuracy of about
+/- 62 metres (0.03 miles) within a few minutes of PLB activation and a non-GPS PLB
within about +/- 5km (3 miles) and typically within 45 minutes.
PLBs also have a secondary homing transmitter. This transmits on the 121.5 MHz
internationally recognised aviation guard channel. When the rescue services get close
they can "home in" on this signal using direction finding techniques.
More than 22,000 lives have been saved by distress signals routed via the COSPAS-
SARSAT* system since it was installed in 1996.
+/- 62 metres (0.03 miles) within a few minutes of PLB activation and a non-GPS PLB
within about +/- 5km (3 miles) and typically within 45 minutes.
PLBs also have a secondary homing transmitter. This transmits on the 121.5 MHz
internationally recognised aviation guard channel. When the rescue services get close
they can "home in" on this signal using direction finding techniques.
More than 22,000 lives have been saved by distress signals routed via the COSPAS-
SARSAT* system since it was installed in 1996.
* For a full explanation, visit the Cospas-Sarsat web site:
http://www.cospas-sarsat.org
How does your PLB work?
The PLB has two radio transmitters which start transmitting when you activate the
PLB. One transmitter operates at 406 MHz which transmits alerts via satellites. The
other operates at 121.5 MHz which transmits a signal which can be received by over-
flying aircraft and Search and Rescue homing receivers.
Ground stations track the satellites and process the distress signals to obtain a
location of the distress. The processed information is then forwarded to a Mission
Control Centre where it is combined with PLB registration information and passed to a
Rescue Coordination Centre which alerts the appropriate Search and Rescue
authorities. Successive satellite passes refine and confirm the original information.
PLBs with inbuilt GPS receivers determine their own geographical position and
transmit it as part of the distress alert signal. Locations where the sky area is
obscured significantly, such as under a tree canopy or in a steep-sided canyon, may
result in delays in GPS position fixing. In extreme circumstance, the PLB may fail
PLB. One transmitter operates at 406 MHz which transmits alerts via satellites. The
other operates at 121.5 MHz which transmits a signal which can be received by over-
flying aircraft and Search and Rescue homing receivers.
Ground stations track the satellites and process the distress signals to obtain a
location of the distress. The processed information is then forwarded to a Mission
Control Centre where it is combined with PLB registration information and passed to a
Rescue Coordination Centre which alerts the appropriate Search and Rescue
authorities. Successive satellite passes refine and confirm the original information.
PLBs with inbuilt GPS receivers determine their own geographical position and
transmit it as part of the distress alert signal. Locations where the sky area is
obscured significantly, such as under a tree canopy or in a steep-sided canyon, may
result in delays in GPS position fixing. In extreme circumstance, the PLB may fail