Section 7, The search and rescue system, General overview – ACR&Artex SATELLITE2 406 User Manual
Page 16: Satellite detection
Y1-03-0148-2 Rev. M
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For both models
Always refer battery replacement and any 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
and doing a full functional test on the unit.
NOTE: There are no user serviceable items inside the beacon. DO NOT OPEN THE BEACON EXCEPT TO DISABLE
IN CASE OF FAULTY ACTIVATION. Otherwise, always have beacon serviced by an authorized Battery Replacement
Center. For the nearest location of a Battery Replacement Center, visit our website at
NOTE: THE BEACON MAY OR MAY NOT REQUIRE SPECIAL SHIPPING INSTRUCTIONS DUE TO THE LITHIUM
BATTERIES AND CHANGES IN SHIPPING REGULATIONS. PLEASE REFER
TO ACR’S WEBSITE
FOR PROPER SHIPPING INSTRUCTIONS.
6.3
Shore Based Maintenance (SBM) for SOLAS Vessels, IMO MSC/Circ. 1039
The Maritime Safety Committee approved guidelines for shore-based maintenance of satellite beacons, for the
purpose of establishing standardized procedures and minimum levels of service for the testing and maintenance of
satellite beacons. First Shore Based Maintenance on all ACR EPIRBs is due at the date of the first battery
replacement.
6.4
Annual Testing for SOLAS Vessels, IMO MSC/Circ. 1040
SOLAS regulation IV/15.9 dictates annual testing of 406 MHz satellite EPIRBs. Testing should be carried out using
suitable test equipment capable of performing the relevant measurements. All checks of electrical parameters should
be performed in the self-test mode, if possible.
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
RapidFix™ can also transmit a distress alert (acquired by the internal or external 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, what type of vessel you have, your homeport, 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. 406 MHz beacons are required to have their registration updated every two
years.
*The national authority is the governmental body responsible for EPIRB registration database administration for the
country for which the EPIRB is programmed.
Once the 406 MHz signal is relayed through the LEOSAR and/or GEOSAR network, SAR forces determine who is
closest, and then proceed to the beacon using the 121.5 MHz homing frequency.
7.2
Satellite Detection
EPIRBs transmit to the satellite portion of the COSPAS-SARSAT system. COSPAS-SARSAT is an international
system that utilizes Russian Federation 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 EPIRBs 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.