ACR Electronics PLB-350B Installation instructions

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CAUTION: Before proceeding to install, test or use your new
ACR Electronics’ product, please read this Product Support Manual
in its entirety.
If you have questions regarding the contents of the manual or
something not covered in the manual, please contact our Technical
Service Department at ACR Electronics, Inc., Telephone +1 (954)
981-3333. You can also visit our website at
www.acrelectronics.com and access the Frequently Asked
Questions (FAQs) section for further information. If in the future you
lose this manual, you may access and print a replacement on the
ACR website.
PLEASE READ ALL WARNINGS, CAUTIONS AND
NOTES CAREFULLY
About Cobham Life Support, ACR Products
Cobham Life Support, ACR Products www.acrelectronics.com,
designs and manufactures a complete line of safety and survival
products including EPIRBs, PLBs, AIS, SARTs, Strobe Lights, Life
Jacket Lights, Search Lights and safety accessories. The quality
systems of this facility have been registered by UL to the ISO
9001:2000 Series Standards. Recognized as the world leader in
safety and survival technologies, ACR has provided safety
equipment to the aviation and marine industries as well as to the
military since 1956.
About Cobham plc
Cobham plc is an international company engaged in the
development, delivery and support of advanced aerospace and
defense systems for land, sea, air and space. The company has
four divisions that collectively specialize in the provision of
components, subsystems and services that keep people safe,
improve communications and enhance the capability of aerospace
and defense platforms.

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Table of Contents
STEP ONE - REGISTERING YOUR BEACON _____________________ 3
STEP TWO - HOW THE BEACON WORKS ______________________ 5
STEP THREE - MAINTAINING YOUR PLB______________________ 13
APPENDIX A - ACCESSORIES _______________________________ 17
APPENDIX B - THE COSPAS-SARSAT SYSTEM___________________ 19
APPENDIX C - TECHNICAL SPECIFICATIONS ____________________ 20
APPENDIX D - WARRANTY, USEFUL LIFE POLICY, NOTICES ________ 21
NOTE re: Applicable products
This manual supports all configurations of PLB-350B beacons. In addition
to the part numbers listed on the cover page, other configurations of these
products may be available, thus you may have purchased a product
configuration with a different version of the part number (for example,
2880.63). As long as the first four digits are the same as one of the part
numbers on the cover, this manual is applicable.

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STEP ONE - REGISTERING YOUR BEACON
Why is registration important?
As the owner of this 406 MHz beacon, it is mandatory that you register
it with the PLB national authority of your country: It is the law. Please
note that all 406 MHz beacons are required to have their registration
updated every two years by the owner.
HOW REGISTRATION WORKS:
All 406 MHz beacons transmit a Unique Identifier Number (UIN) when
activated. This UIN is programmed into the beacon based on the
country in which the beacon is registered, thus authorities are able to
determine which country’s database will have your registration
information. SAR forces will have information as to who you are as the
owner of the beacon, the name and type of vessel that you have (if
applicable), your address, and who to contact that might know of your
current situation - but only if your beacon has been properly registered.
Valuable search and rescue resources are wasted every year
responding to false alerts, and registering your beacon helps to resolve
this quickly.
Your personalized ID code
programmed inside each beacon is
transmitted to Search and Rescue
(SAR). SAR forces use this code to pull
up your registration to find out valuable
information about who needs help.
YOUR RESCUE WILL
BE DELAYED IF YOUR
BEACON ISN’T PROPERLY
REGISTERED!

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What country should I register in?
The beacon must be registered in the country of the owner’s residence.
If the beacon is not programmed to that country’s code and protocol,
and the residence is outside of the USA, the beacon needs to be
reprogrammed.
Additionally, the beacon must be reprogrammed if you, as the owner,
move out of the country where the beacon is registered. To verify the
country for which a beacon is programmed, see the label with the UIN
(Unique Identification Number) on the back of the unit.
How do I register?
Registration in the United States
The national authority that accepts registrations in the United States is
the National Oceanic and Atmospheric Administration (NOAA).
There are three ways to register:
1. The fastest and easiest way to register is online at
www.beaconregistration.noaa.gov/.
2. Faxing a registration is also acceptable. Fax the registration form to
the fax number on the top of the registration form.
NOTE: Do not confuse the registration form with the ACR Electronics
warranty card.
3. If online or fax registration is not available, mail the registration form
with the pre-addressed, postage paid envelope to:
Registration NOAA/NESDIS
NSOF, E/SP3
4231 Suitland Road
Suitland, MD 20746
All registration forms will be entered in the 406 MHz beacon registration
database within 48 hours of receipt. The information you provide on the
registration form is used for rescue purposes only.
A confirmation letter, a copy of the actual registration and a proof-of-
registration decal will be mailed to you within two weeks. When you
receive these documents, please check the information carefully,
and then affix the decal to your beacon in the area marked “BEACON
DECAL HERE.” It is very important that the proof of registration
decal matches the UIN on the beacon. If you do not receive
confirmation back from NOAA within two weeks, call toll free (888) 212-
7283 for assistance.

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Registration in Canada
Canadian residents can register online at:
http://canadianbeaconregistry.forces.gc.ca/ or contact the Canadian
Beacon Registry by phone at: 877-406-7671 or by fax at: 877-406-3298.
Canadian Beacon Registry
CFB Trenton, PO Box 1000 Stn Forces
Astra, Ontario K0K 3W0
Registration in Other Countries
In countries other than the United States and Canada, 406 MHz
beacons are registered with that country’s national authority at the time
of purchase. The sales agent may have assisted you in filling out the
forms and sending them to the country’s national authority. Alternatively,
many countries allow online registration in the International 406 MHz
Beacon Registration Database (IBRD) at www.406registration.com.
To verify that the unit is properly programmed for your country, view the
UIN label on the back of the unit. In the event that the beacon is not
programmed for your country, the sales agent (if properly equipped) can
reprogram the unit for the correct country.
STEP TWO - HOW THE BEACON WORKS
1. How your beacon brings help
406 MHz beacons are a type of portable emergency equipment that
transmits a distress signal to search and rescue (SAR) organizations.
The purpose of these beacons is to aid SAR teams in tracking and
locating ships or individuals in jeopardy as rapidly as possible.
The 406 MHz frequency is a worldwide dedicated emergency frequency
that is detected by a network of satellites called the Cospas-Sarsat
system. This satellite system was established by, and continues to be
supported by, its primary benefactors - the USA, Russia, Canada and
France. The Cospas-Sarsat system has saved over 28,400 lives - and
counting - since its inception. See Appendix or the Cospas-Sarsat
website for more information about the system at www.cospas-
sarsat.org.
When a 406 MHz beacon is activated, the digital distress message is
sent to Cospas-Sarsat satellites and, in turn, the distress message is
relayed to SAR. The distress message contains the beacon UIN and on
some models the GPS location of the beacon. Additional information
about the beacon is accessed by SAR from the beacon registration
database. At the same time the 406 MHz signal is activated, a 121.5
MHz signal is turned on. The 121.5 MHz signal is used by SAR to home
in on the beacon as they approach it.

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The 406 MHz signal is detected by multiple satellites and from that
information the location of the beacon can be calculated. This data
alone is sufficient for SAR to find persons or ships in distress in a
reasonable timeframe. However, as a further enhancement, some
beacons have a GPS engine onboard. This feature allows the beacon to
acquire current location coordinates from an internal GPS receiver. The
purpose of this feature is to send an even more precise location of the
beacon to the satellites, i.e., latitude and longitude data. This helps SAR
to reach the location even faster.
2. Internal GPS position system
The PLB-350 is fitted with an internal GPS receiver that will determine
the coordinates (latitude and longitude) of the beacon’s position on the
globe, to be transmitted to the Cospas-Sarsat emergency system.
When the beacon is activated, the internal GPS immediately attempts to
acquire positional coordinates. GPS coordinates can be acquired any
time that the GPS is on, but only valid data is saved. Once the beacon
acquires valid coordinates, the data is included as part of the next
transmitted 406 MHz digital message.
The internal GPS operates on a schedule during a beacon activation.
The GPS is on for a time, actively acquiring coordinates, and off for a
time, in a standby state. The schedule is designed to conserve battery
but, at the same time, assure that navigational coordinates are regularly
updated.

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3. Anatomy of your beacon
NOTE: The appearance of your beacon may vary from this picture.
Figure 1
Antenna
Latch
FRONT BACK
GPS antenna
location
Antenna:
Wrapped
around
beacon
UIN Label: Applied at
the factory, the 15
character hexadecimal
number is unique to
each beacon.
Activation
button cover
Battery expiration label
with the month/ year
the battery needs to be
replaced.
Keypad
Multi-language label:
This optional label may
be applied for ease of
use.
Registration decal
supplied by some
countries: Once the
beacon is registered,
the label goes here.
Antenna
latch

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4. Distinguishing PLB Features
The distinguishing features available on your PLB vary with the
particular model that you selected. The following table summarizes the
similarities and differences in models.
PLB-350B
Product
names
AquaLink™ 406 GPS PLB
SARLink™ 406 GPS PLB
ACR
Product
Number
2882
2883
Unique
features
LED strobe, 12 GPS acquisition tests
GPS engine
Internal, 66-channel GPS receiver
Top case
Clear
Buoyant
Yes
No
Included
Accessories
Attachment Clip
Multi-Function Belt Clip
Optional
Accessories
Flotation pouch (ACR P/N 9504)
5. Activating your beacon
Overview
Personal Locator Beacons are designed to be manually activated. They
are only to be activated when all other means of self-rescue have been
exhausted. When properly registered as required, the activation of the
beacon tells Search and Rescue who you are, where you are, and that
you are facing a life threatening situation.
WARNING: This transmitter is authorized for use only during
situations of grave and imminent danger. Deliberate misuse may incur
a severe penalty.

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NOTE: The appearance of your key pad may vary from this picture.
Figure 2 - Key Pad Functions
NOTE: If you notice the PLB is flashing the red or green LED and
“beeping” periodically on its own, this likely means it has accidentally
been activated and needs to be shut off and reported as a false alert see
section on false alerts.
Activation
diagram
When activated:
(Red LED) transmitting
406 MHz during
activation
(Green LED) 406 MHz
includes GPS data
(IR LED) Programming
Interface
(Not owner accessible)
Self-test /
GPS Test Button
ON / OFF Button
(visible only when
antenna is deployed)

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6. Activation (406 MHz and 121.5 MHz)
To activate your beacon in a distress situation, follow these steps (see
Figure 3 below).
1) Unfasten the antenna from the case.
2) Move it into the upright position
3) Depress the ON/OFF ( ) button for 1 full second.
You will hear a “beep” and your beacon is now activated. While
transmitting your distress signal, the red LED will flash once every 2
seconds, alerting you that your beacon is active. An additional “beep”
will sound every time your beacon transmits data to the satellites
(roughly every 50 seconds).
7. 406 MHz/121.5 MHz antenna position
For maximum performance you must deploy the beacon antenna into
the proper position as shown in Figure 3. If at all possible, be sure the
antenna is positioned facing the sky and avoid submerging in water.
This device is intended to operate on or above the ground or while
attached to your person above the water line.
8. Activation with GPS
If your unit is activated, the GPS receiver will start up, search to find
your LAT/LON and incorporate it into your 406 MHz signal. As soon as
the GPS receiver acquires valid positioning data, the red LED will stop
blinking and the green LED will begin flashing once every 2 seconds.
The same GPS data will be sent with each 406 MHz signal for the next
twenty minutes. At that time the internal GPS will start up again, search
to find your LAT/LON and incorporate it into your next 406 MHz signal. If
for any reason the internal GPS cannot update your LAT/LON, your last
position will be used for the next four hours. At that time the green LED
Figure 3




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Figure 4 –GPS Receiver Location
will stop blinking and the red LED will flash once every 2 seconds until
new GPS data is obtained.
9. GPS receiver orientation
When activated, it is critical that you do not cover the beacon with any
body part, water, clothing, etc. The GPS receiver is located under the
bottom portion of the case behind the product logo (see Figure 4).
To ensure optimum performance of the GPS receiver, the beacon needs
to have an unobstructed view of the sky. Avoid submerging the GPS
receiver in water if possible. Water will shield and inhibit the GPS
receiver and may cause difficulties obtaining your GPS coordinates.
Avoid leaning over the beacon to view blinking LED as you may shield
the GPS reception.
10. Turning off the beacon
To deactivate your beacon, depress the ON/OFF ( ) button for 1 second.
Once the beacon is deactivated, all blinking LED’s will stop, signifying that
the beacon is no longer sending your distress message.
If deactivation should fail, remove the six screws holding the unit together
and unplug the battery to disable the unit. Return the beacon to ACR
Electronics for service.
NOTE: Leave beacon on until rescued. Turning beacon off will prolong or
prevent rescue. Repeated activations could be viewed as a hoax.

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11. Preventing false alerts
A false alert is any activation of the beacon, intentional or otherwise,
that does not result from a situation of grave and imminent danger.
Be sure to do the following to help minimize false alerts:
Register your beacon. This does not reduce false alert rates;
however, when the beacon is properly registered, the situation can
usually be resolved with a phone call.
Be careful with whom you leave your beacon. Make sure that
they know how to use it, and that they understand the ramifications
of causing a false alert. A lot of false alerts are generated by curious
individuals. If you notice the beacon is flashing the red or green LED
and “beeping” periodically on its own, this likely means it has
accidentally been activated and needs to be shut off and reported.
Do not stow beacon while other gear is in contact with the
keypad.
The Cospas-Sarsat satellites detect distress beacon transmissions
immediately and locate the transmission within a few minutes of beacon
activation.
NOTE: If you report a false alert and the authorities have not received
the signal, do not be concerned. This may mean that you were able to
deactivate the beacon before transmitting the signal.
12. False alert
A false alert must be reported to the search and rescue authorities.
False alerts in the USA that are rectified must be reported to the US Air
Force Rescue Coordination Center (AFRCC) to let them know that the
situation has been corrected and everything is fine. Responsibly
reporting these events to the AFRCC or your proper authority will not
incur a penalty, but deliberate misuse or not notifying the proper
authority may incur a severe penalty.
Reporting
Should there be a false alert for any reason, it must be reported to the
nearest search and rescue authorities. The information that should be
reported includes:
// The PLB 15-digit Unique Identifier Number (UIN)
// Time and date
// Duration and cause of activation
// Location of beacon at the time of activation
To report false alert in the United States,contact the AFRCC:
United States Air Force Rescue Tel: [phone]
Coordination Center (AFRCC)

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To report false alerts outside of the USA, contact the national
authority where your beacon is registered.
STEP THREE - MAINTAINING YOUR PLB
1. Routine Maintenance
Carefully inspect the beacon case for any visible cracks. Cracks may
admit moisture, which could falsely activate the beacon or otherwise
cause a malfunction. Any cracks observed should be immediately
referred to ACR for evaluation by calling [phone]. ACR
Technical Support can also be reached by sending an email to
[e-mail].
After checking the beacon case for cracks, it may be wiped down with a
clean, damp cloth. Do not use any type of cleaner on your beacon.
2. Battery Replacement
Replace the battery no later than 6 years from date of manufacture, 5
years from date of install, or after emergency use. 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 battery replacements and other beacon
service to a factory authorized Battery Replacement 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. Opening the beacon will void the warranty.
WARNING: This device is life saving equipment. The battery
chemistry, make and construction are controlled by regulation. Battery
service may only be performed by factory-trained personnel with OEM
parts tested to meet the applicable standards and retain approvals.
Unauthorized service may also result in the product failing to perform in
an emergency. Ask your service center if they have been specifically
authorized by ACR to service this product, and do not leave the beacon
with them if they are not an ACR Battery Replacement Center (BRC).
Visit our website http://www.acrelectronics.com, email us at
[e-mail] or call [phone] for a listing of
authorized Battery Replacement Centers nearest you.
For the nearest location of a Battery Replacement Center, visit our
website at www.acrelectronics.com. Click on “Battery Replacement
Center”.
This beacon contains two (2) lithium metal battery packs that are less
than 2 grams each. They are not classified as Hazmat for transportation.
Prior to shipping beacon for service, alert your carrier about the

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batteries contained in this equipment to make sure they properly label
your package. Call ACR’s Technical Service department at +1 (954)
981-3333 for proper shipping instructions or visit the ACR website in the
Support section entitled “Hazmat, MSDS Sheets, & Info”.
3. Self-Test
ACR strongly recommends performing a Self-test once per month, or at
least two weeks prior to a trip, to allow enough time for service, should
your beacon require it.
A Self-test is initiated by holding the Self-test button ( ) for at least 1
second and less than 5 seconds. Your beacon will sound an initial
“beep”and flash the green LED to signify the test has begun. Four more
beeps will follow. The green LED will flash a second time to indicate
that the Self-test was successful.
NOTE: The “beep”is a very high pitch sound that some people are
unable to hear. Watching the LEDs may be more useful to you.
Components Tested: Data integrity and memory, 406 MHz
synthesizer, RF power/battery, GPS header (if equipped).
If a red LED flashes at the completion of the Self-test, your beacon has
failed. Repeat the Self-test. If the failure persists, contact ACR
Electronics or an authorized Battery Replacement Center to have your
beacon serviced.
NOTE: During a Self-test your beacon will send a 406 MHz signal coded
as self-test to the satellite system. The 121.5 MHz homing signal is
inhibited during Self-test. This allows you to test your beacon any time
during the day without causing false alerts.
Self-Test Sequences
Self-Test Guide
( Green LED Red LED)
Green LED with beep, 4
additional “beeps”, Green LED,
strobe flash
Successful Self-test
Green LED, Less than 4 “beeps”,
Red LED
Failed Self-test: Return unit
to ACR for service
Red LED with beep, 4 additional
“beeps”, Green LED, strobe flash
Successful Self-test: Less
than 24 hours of
transmission life is left in the
batteries.
Red LED with or without beep,
Less than 4 additional “beeps”,
Red LED, strobe flash (PLB-350B
only)
Failed Self-test: Return unit
to ACR for service. Less
than 24 hours of
transmission life is left in the
batteries.

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4. Battery witness seal failure
If your beacon flashes an initial red LED at the beginning of the Self-
test, this indicates that your electronic witness has been broken and you
have used more than the allotted battery life for self-testing. While the
beacon will still operate normally in a distress situation, ACR strongly
recommends you have your battery replaced and the electronic witness
reset to ensure that you will have 24 hours of battery power.
5. GPS acquisition test
This test is NOT required as 100% of all GPS receivers that leave ACR
have been tested to ensure they perform correctly. However, if you would
like to ensure your GPS receiver is working, please follow these
instructions very closely.
CAUTION: The following test should not be performed more than
twelve times during the life of the battery pack. Once this GPS testing
feature reaches 12 times, the feature will be disabled by internal software
until the battery is replaced.
NOTE: The GPS receiver is located under the bottom front portion of the
case. It is imperative that the receiver is not obstructed during the GPS
acquisition test or activation to ensure that the GPS receiver is acquiring
your latitude (LAT) and longitude (LON) position. This test must be
performed outside with a clear view of the sky.
Press the Self-test button for greater than 5 seconds. Observe the beacon
for the entire GPS test. A beep and green LED will indicate that the GPS
has been turned ON. The beacon will beep every 5 seconds and the GPS
will remain ON until LAT/LON coordinates have been obtained or until 2
minutes have elapsed. If good LAT/LON data has been obtained, a single
406 MHz test signal will be sent out with location data and the GPS will be
turned OFF and the green LED will light for at least 3 seconds along with a
long beep. This LAT/LON data is not saved for use. The green LED
indicates that the GPS is functioning properly and that the beacon is in a
location or environment where it can receive the necessary signals from
satellites. If the GPS does not acquire good LAT/LON data, the GPS will
turn OFF after 2 minutes, followed with a RED LED light up for 3 seconds
along with a long beep, and no 406 MHz signal will be sent out.
GPS Test Sequences (max. 2
minutes 50 seconds)
GPS Test Guide
Green LED and beep at start
followed by continuous beeps every 5
seconds, Green LED & Long beep
Successfully acquired GPS
data, 406 MHz signal sent out
with location data
Green LED and beep at start
followed by continuous beeps every 5
seconds, Red LED & Long beep
GPS data was not successfully
acquired, no signal sent out.

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6. Changing ownership or contact information
As the owner of the beacon, it is your responsibility to advise the national
authority of any change in your registration information. If you are
transferring the beacon to a new owner, you are required to inform the
national authority. You can do this by using their online database or by
letter, fax or telephone and informing the authority of the name and address
of the new owner.
The new owner of the beacon is required to provide the national
authority with all of the information requested on the registration form.
This obligation transfers to all subsequent owners. See earlier section,
STEP ONE, for further details on this process.
7. Lost or stolen PLBs
If your PLB is lost or stolen, do the following immediately:
// Report to your local authorities that the PLB has been lost or stolen
// Contact NOAA at [phone] (212-SAVE), or your national
authority, with the following information:
oPolice department name
oPolice department phone number
oPolice case number
If your PLB were to be activated, the information you provided will be
forwarded to the appropriate search and rescue authorities who will
ensure that your PLB gets back to you. If someone attempts to register
a PLB reported as stolen, NOAA or your national authority will notify the
appropriate police department.

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Figure 5 - Belt Clip
APPENDIX A - ACCESSORIES
1. Multi-Function Belt Clip
The SARLink™ comes standard with a multi-
function belt clip. To install the clip, simply align
the bottom tabs on the clip with the insert holes
located on the bottom of the beacon. Snap the
clip in place by pressing the top of the clip so
that the two top tabs engage in the two insert
holes on the top of the beacon (see Figure 5). To
remove the clip, push up and back on the top
tabs one at a time to disengage the clip from the
beacon.
The belt clip has been designed to
accommodate your extreme adventures.
You can secure your beacon directly to
backpack webbing straps, life jackets or belts to ensure the beacon is
close at hand. ACR recommends that you secure your beacon
someplace on your person that is easily accessible in case of an
emergency for rapid activation. Ensure the beacon is secured firmly and
is protected before heading out to avoid damage or loss.
NOTE: ACR recommends that once you have clipped your beacon
in place that you also anchor the beacon with the lanyard to your life
jacket, backpack, etc. to ensure the unit will not be lost if it should
break out of the clip.

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Figure 6 –
Attachment Clip
2. Attachment Clip
The AquaLink™ comes standard with an
attachment clip. To install the clip, simply align the
bottom tabs on the clip with the insert holes
located on the bottom of the beacon. Snap the
clip in place by pressing the top of the clip so that
the two top tabs engage in the two insert holes on
the top of the beacon (see Figure 6). To remove
the clip, push up and back on the top tabs one at
a time to disengage from the beacon.
This clip has been designed to secure your
beacon directly to life jacket webbing straps or
belts to ensure the beacon is close at hand. ACR
recommends that you have a strap on your life
jacket in the shoulder area for attachment of the
PLB. The beacon should hang with the GPS
receiver up (so that the beacon is inverted). This
will give the GPS receiver the best possible view
of the sky. It is also recommended that you try
your life jacket on in the water to see how you
float in it and where to best locate the beacon so that the beacon is not in
the water. You may choose to carry your beacon in a pocket but you
should have a strap installed on your life jacket to attach the beacon
when it is activated. This will leave your hands free while treading water.
NOTE: ACR recommends that once you have clipped your beacon in
place that you also secure the beacon with the lanyard to your life
jacket, backpack, etc. to ensure the unit will not be lost if it should
break out of the clip.

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APPENDIX B - THE COSPAS-SARSAT SYSTEM
1. General overview
Beacons transmit to the satellite portion of the Cospas-Sarsat system. Cospas-
Sarast satellites are 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-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
asure 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.
The addition of the GEOSAR satellite system greatly improves the reaction time
for a SAR event. This satellite system has no Doppler capabilities at 406 MHz,
but will relay the distress alert to any of the LUT stations. When there is GPS
data included in the distress message, SAR authorities instantly know your
location to within 110 yards (100 m). This speeds up the reaction time by not
having to wait for one of the LEOSAR satellite to pass overhead. Because most
of the search and rescue forces presently are not equipped to home in on the
406 MHz Satellite beacons signal, homing must be accomplished at 121.5 MHz.
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.
2. Global Positioning System (GPS)
The GPS system is a satellite group that enables a GPS
receiver to determine its exact position to within 30 m (100
ft.) anywhere on earth. With a minimum of 24 GPS
satellites orbiting the earth at an altitude of approximately
11,000 miles they provide users with accurate information
on position, velocity, and time anywhere in the world and in all weather
conditions. Beacons that have GPS engines add this data to its distress
transmission, allowing search and rescue forces to narrow the search to a very
small area, thus minimizing the resources required, and dramatically increasing
the effectiveness of the overall operation.