ACR Electronics PLB-300 User Manual
Y1-03-0228 Rev. B
11
6.2
Battery Replacement
The battery must be replaced by the date indicated on the beacon or every five (5) years. At each inspection,
check the time remaining until replacement is required. The battery should be replaced if the beacon has been
activated for any use other than the self test. Always refer all long life battery replacement and other beacon
service to a factory authorized service center. Battery replacement includes servicing the beacon by replacing
all o-rings, testing the water seal and the electrical properties.
NOTE: There are no user serviceable items inside the beacon. DO NOT OPEN THE BEACON.
For the nearest location of a Battery Replacement Center, visit our website at
The battery must be replaced by the date indicated on the beacon or every five (5) years. At each inspection,
check the time remaining until replacement is required. The battery should be replaced if the beacon has been
activated for any use other than the self test. Always refer all long life battery replacement and other beacon
service to a factory authorized service center. Battery replacement includes servicing the beacon by replacing
all o-rings, testing the water seal and the electrical properties.
NOTE: There are no user serviceable items inside the beacon. DO NOT OPEN THE BEACON.
For the nearest location of a Battery Replacement Center, visit our website at
The beacon may or may not require special shipping instructions due to the lithium batteries and changes in
shipping regulations.
Call ACR’s customer service department at +1 (954) 981-3333 ext. 2110 for proper
shipping instructions.
SECTION 7
– THE SEARCH AND RESCUE SYSTEM
7.1
General Overview
Beacons provide distress alerts via radio transmission on 406 MHz to the LEOSAR satellites of the COSPAS -
SARSAT network. The ResQFix™ and MicrOFix™ can also transmit a distress alert (acquired by the internal
GPS) to the GEOSAR network that includes GPS latitude and longitude coordinates.
The message transmitted is unique for each beacon, which provides identification of the transmitter through
computer access of registration files maintained by the National Oceanic and Atmospheric Administration or
other national authority*. Remember, SAR forces will know who you are and who to contact that might know of
your current situation only if your beacon has been properly registered. This will help expedite the launch of a
rescue operation.
NOTE: 406 MHz beacons are required to have their registration updated every two years.
*The national authority is the governmental body responsible for beacon registration database administration
for the country for which the beacon is programmed.
Once the 406 MHz signal is relayed through the LEOSAR and/or GEOSAR network, SAR forces determine
which SAR group is closest. This group proceeds to the beacon using the 121.5 MHz homing frequency.
Beacons provide distress alerts via radio transmission on 406 MHz to the LEOSAR satellites of the COSPAS -
SARSAT network. The ResQFix™ and MicrOFix™ can also transmit a distress alert (acquired by the internal
GPS) to the GEOSAR network that includes GPS latitude and longitude coordinates.
The message transmitted is unique for each beacon, which provides identification of the transmitter through
computer access of registration files maintained by the National Oceanic and Atmospheric Administration or
other national authority*. Remember, SAR forces will know who you are and who to contact that might know of
your current situation only if your beacon has been properly registered. This will help expedite the launch of a
rescue operation.
NOTE: 406 MHz beacons are required to have their registration updated every two years.
*The national authority is the governmental body responsible for beacon registration database administration
for the country for which the beacon is programmed.
Once the 406 MHz signal is relayed through the LEOSAR and/or GEOSAR network, SAR forces determine
which SAR group is closest. This group proceeds to the beacon using the 121.5 MHz homing frequency.
7.2
Satellite Detection
Beacons transmit to the satellite portion of the COSPAS - SARSAT system. COSPAS - SARSAT is an
international system that utilizes Russian Feder
Beacons transmit to the satellite portion of the COSPAS - SARSAT system. COSPAS - SARSAT is an
international system that utilizes Russian Feder
ation and United States’ low altitude, near-polar orbiting
satellites (LEOSAR). These satellites assist in detecting and locating activated 406 MHz satellite beacons.
COSPAS and SARSAT satellites receive distress signals from beacons transmitting on the frequency of 406
MHz. The COSPAS - SARSAT 406 MHz beacon signal consists of a transmission of non-modulated carriers
followed by a digital message format that provides identification data. The 406 MHz system uses Satellite-
borne equipment to measure and store the Doppler-
COSPAS and SARSAT satellites receive distress signals from beacons transmitting on the frequency of 406
MHz. The COSPAS - SARSAT 406 MHz beacon signal consists of a transmission of non-modulated carriers
followed by a digital message format that provides identification data. The 406 MHz system uses Satellite-
borne equipment to measure and store the Doppler-
shifted frequency along with the beacon’s digital data
message and time of measurement. This information is transmitted in real time to an earth station called the
Local User Terminal (LUT), which may be within the view of the satellite, as well as being stored for later
transmission to other LUTs.
The LUT processes the Doppler-shifted signal from the LEOSAR and determines the location of the beacon,
then the LUT relays the position of the distress to a Mission Control Center (MCC) where the distress alert and
location information is immediately forwarded to an appropriate Rescue Coordination Center (RCC). The RCC
dispatches Search and Rescue (SAR) forces.
Local User Terminal (LUT), which may be within the view of the satellite, as well as being stored for later
transmission to other LUTs.
The LUT processes the Doppler-shifted signal from the LEOSAR and determines the location of the beacon,
then the LUT relays the position of the distress to a Mission Control Center (MCC) where the distress alert and
location information is immediately forwarded to an appropriate Rescue Coordination Center (RCC). The RCC
dispatches Search and Rescue (SAR) forces.