Personal Locator Beacons (PLBs) are portable units that operate much the same as Emergency Locator Transmitters (ELTs). These beacons are designed to be carried by an individual person but can also be carried on a boat or aircraft. Unlike emergency locator transmitters, they can only be activated manually and operate exclusively on 406 MHz. And like emergency locator transmitters  all personal locator beacons also have a built-in, low-power homing beacon that transmits on 121.5 MHz. This allows rescue forces to home in on a beacon once the 406 MHz satellite system has gotten them "in the ballpark" (about 2-3 miles).Some newer PLBs also allow GPS units to be integrated into the distress signal.This GPS-encoded position dramatically improves the location accuracy down to the 100-meter level…that’s roughly the size of a football field!  All this is available in a unit small enough to fit in a pocket and with the push of one button.

Prior to July 1st, 2003 only residents of Alaska had been able to use personal locator beacons. The Alaska PLB Program was set up to test the capabilities of PLBs and their potential impact on SAR resources. Since March of 1995, the experiment proved very successful and helped save nearly 400 lives while generating only a few false alerts. The success of the Alaska PLB program undoubtedly paved the way for nationwide usage of these devices.  PLBs are now available to anyone worldwide.

Here's how it works: When activated, a personal locator beacon transmits a digitally coded signal on the 406 MHz frequency. This signal is received by a COSPAS, SARSAT or GOES satellite and relayed to a ground station. The ground station calculates the PLB location and transmits the information to a Mission Control Center. The MCC recognizes these specially coded beacons as personal locator beacons and transmits a distress message directly to a Rescue Coordination Center (RCC). The RCC then uses state, local or federal assistance to conduct the rescue.  Since all beacons must be registered, the RCC also has all the information for the person who registered the beacon so rescue crews know who to contact (relatives, friends, etc.) to get any additional information on the person/people activating the PLB.  Personal locator beacons can be used anywhere in the world.  Although they are programmed for each specific country, they can be used and detected in any country and in any place on the planet. 

Most personal locator beacons weigh less than a pound (many in the 8-9oz range), can fit in a pocket, are waterproof, and have a usable shelf life (battery life) of 5 to 7 years.  Like many products, the price of personal locator beacons can be related to size and options.  The smaller and lighter the unit or if it has GPS built into it, the more expensive it can be.  Most PLBs cost between $300 and $600.  Once activated or if the battery life is exceeded, the unit must be sent to an authorized repair center to have the battery replaced and all the functions of the unit tested.  All personal locator beacons are required by law to be registered with NOAA at www.beaconregistration.noaa.gov.

List of Personal Locator Beacon FAQs 

What services can I use to send messages with my PLB?
How does the optional messaging service work?
What is a Self Test?
How often should I carry out a Self Test?
What is a GPS Self Test?
What does a Self Test check?
What is a Through Satellite Self Test?
What does a Through Satellite Self Test check?
What are the advantages of a Through Satellite Self Test?
Are there any Beacons that I can't test Through the Satellites?
What happens if I set off a false alert by mistake?
How do I carry out a Through Satellite Self Test?
What should I do if I get a Self Test failure?
What if the Through Satellite Self Test Doesn't Work?
What does it cost to have the battery replaced?

What services can I use to send messages with my PLB?

There are two services that recently became available that can be used to provide messaging using almost any personal locator beacon.  To see which beacons have this capability click here.  These two companies that offer this service use special satellites that transmit a signal from a personal locator beacon (PLB), emergency locator transmitter (ELT), and a emergency position indicating radio beacons (EPIRB) to an email address or cell phone via text message. The service cost is typically between $40 to $60 per year.  It does allow the ability to send a preset message of the users choice (depending on service) and the location of the PLB that can be seen on a map by anyone receiving the message using the following websites.  For non-ACR Beacon users: www.safelifesystems.com, and for ACR Beacon users (SARLink and AquaLink): www.406link.com.

How does the optional messaging service work? 

All 4 models of the ACR series personal locator beacons have the ability to send over 400 messages during the life of the battery as long as the position (latitude and longitude) is not sent.  This is done by performing a self test using the self test button ("OK" button if you are using the VIEW series).  The test button must be held for 1 seconds.  The strobe will flash indicating a good test.  (in the VIEW series, the latitude and longitude will also show and an "Good Test" message will appear in the window to indicate a good test.) These messages consist of the "OK" message (up to 30 characters of your choosing).  The "position message" (latitude and longitude) along with the "OK" message can be sent and displayed on a map by those who view the message at the appropriate website.  ONLY 12 "position" messages can be sent with the non-view series (SARLink and AquaLink) over the life of the battery (6 years).  60 "position" messages can be sent with the VIEW series (SARLink View and AquaLink View).  This is done by holding the GPS button or test button on non-View series for 5 seconds.  The basic service ($40/year) allows 1 email and 1 text message to be sent every time a message is sent from the Personal Locator Beacon.  The premium service ($60/year) allows 5 emails and 5 text messages to be sent every time a message is sent from the PLB.  The latitude and longitude are only displayed (VIEW series) when a full test is performed and the "position" message is sent.  There is no way to turn the PLB on/activate the PLB by using the test button.  The antenna must be up (which uncovers the activation button) for the PLB to transmit the emergency signal.

What is a Self Test?

Virtually all 406 MHz personal locator beacons incorporate a self test mode of operation (some very old models of beacon may not have this facility). Standard Self-Tests of beacons usually involve pressing a button or lifting a lever on the beacon and holding it for a few seconds. This usually results in the beacon flashing an LED or Strobe and/or making an audible sound that indicates that the internal circuitry of the beacon is functioning correctly. You should always carefully follow the beacon manufacturers instructions when carrying out a self test as it's possible to get false results or inadvertently trigger a false alarm if you do it incorrectly. If the beacon fails, you should contact the beacon manufacturer or one of their appointed service agents for further advice and instructions. Assuming that the personal locator beacon passes then you can be reasonably confident that it will work correctly in an emergency.

How often should I carry out a Self Test?

The beacon owners' manual usually recommends the frequency of these tests, typical advice is once a month and/or before extended trips or after you suspect that the beacon might have been damaged in some way (e.g. it got dropped) or at the end of the season. For Emergency Locator Transmitters and EPIRBs there are often regulatory requirements that define how often these tests should be performed. You can find further details on these requirements in the relevant beacon section.

What is a GPS Self Test?

Newer GPS (sometimes referred to as GNSS) equipped personal locator beacons may also include an optional GPS Satellite Acquisition Self Test (not all GPS beacons have this facility), which tests the operation of the GPS Receiver and its ability to encode your location into the transmitted distress message. It is not uncommon for this test to only be permitted to be performed once or twice over the life of the battery (e.g. every couple of years), as this type of test can significantly reduce the battery life of the beacon. This is especially true for beacons with an integral GPS receiver; beacons using a separate external GPS receiver can often be tested more frequently. So it is important to think carefully when you want to do this test and to carefully follow the manufacturers' instructions for procedures and recommended frequencies of this optional test as detailed in the User Manual for your beacon. If your personal locator beacon does include this optional test, then assuming that it passes you can have even more confidence in the correct operation of your beacon and especially its ability to send the GPS location of the beacon in an emergency.

Again for Emergency Locator TransmittersLTs and EPIRBs installed in commercial craft there are often regulatory requirements that define how often these tests should be performed. You can find further details on these requirements in the relevant beacon section.

What does a Self Test check?

Assuming that your personal locator beacon has a Self Test facility (and the vast majority do), then when this is activated it checks for the correct operation of the internal circuitry within the beacon and reports the result, usually by flashing an LED or Strobe and/or making an audible sound.
Most importantly it indicates that RF power at 406 MHz is being generated within the beacon and therefore the beacon will probably transmit a signal in an emergency that the Cospas-Sarsat satellites can pick up.

All recent personal locator beacons go one step further than this and actually transmit a single "Self Test" burst that can be picked up by the satellites, which the receiving ground stations are programmed to ignore. This then provides a Self Test facility that with the right equipment can ensure that your beacon is really working correctly (See Through Satellite Self Test).

Some older personal locator beacons also transmit the Self Test burst in the same way that newer beacons do, but not all older beacons work this way, some only carry out the internal check as explained above. You can check whether your beacon actually transmits a Self Test burst or not by looking it up in the list of personal locator beacons here

All personal locator beacons with a Self Test facility check out the internal circuitry within the beacon for correct operation. However the extent of this internal test varies from manufacturer to manufacturer and sometimes between models as well. A typical beacon self test will check out the Battery, 406 MHz Phase Lock Loop (PLL) - the part of the circuitry that makes the beacon transmit at the correct frequency - and the 406 RF output. Some beacons (especially newer ones) check more items than this and a few older beacons may check less. Some beacons also test the 121.5 MHz homing transmitter in the beacon for correct operation as well.

What is a Through Satellite Self Test?

As opposed to a normal Self Test which only checks the internal operation of the personal locator beacon and provides a local indication of pass or fail, a Through Satellite Self Test does just that, it checks that the signal emitted by your beacon can be picked up by the Cospas-Sarsat satellites and can be detected and decoded by the ground stations, thus providing a complete test of the system from end to end.

Normal Cospas-Sarsat Ground Stations ignore Self Test messages, but the SafeLife Systems ground receiving stations have been specially adapted to receive these Self Test messages so that we can provide you with this ultimate level of confidence in the operation of your beacon in an emergency.

What does a Through Satellite Self Test check?

Assuming that your personal locator beacon transmits a message during the Self Test (you can check whether your beacon actually transmits a Self Test burst or not by looking it up in the list of beacons here) then you can use the SafeLife Systems Through Satellite Self Test.

The Through Satellite Self Test carries out a normal Self Test of your beacon and works in exactly the same way as normal, but the transmitted Self Test message is picked up by the SafeLife Systems ground receiving stations and is decoded in the same way that a real message would be to provide the same information that would be provided to the rescue services in the case of an emergency.

Specifically, the ability to determine and provide the following information is available:

Confirmation of whether or not, your personal locator beacon would be detected by the satellites used by the International Search and Rescue network
In addition, you will be provided with the encoded beacon information (15 HEX ID, Country Code, Beacon Type and Programmed Identity) for your verification / records.

In addition, if you have a GPS Personal Locator Beacon that can perform a GPS Self Test then the test can also provide:

The encoded location transmitted as a part of the Beacon message

Also provideed is:

An official Record of the test and the results where this is required to satisfy regulatory or commercial requirements

What are the advantages of a Through Satellite Self Test?

Compared to a normal Self Test a Through Satellite Self Test offers the following advantages:

     -Confidence that you personal locator beacon can transmit a signal that can be picked up by the satellites
     -Confidence that your personal locator beacon transmits a signal that can be recognized and decoded by the ground stations
     -Confidence that the details programmed into your personal locator beacon are correct, thus helping to speed up any rescue should one be necessary at       some point in the future.
     -Overall confidence in the complete system from end to end in case of an emergency
     -If your Personal Locator Beacon is fitted with a GPS Self Test then confidence that the GPS Receiver is working correctly and that the beacon correctly       encodes your location into the transmitted message and that it is received and decoded correctly

Are there any Personal Locator Beacons that I can't test Through the Satellites?

Yes, in particular some older models of Beacon do not transmit a 406 MHz burst, so cannot be tested in this way. In addition some current models of Beacon incorporate features (e.g. a rolled up one time only use antenna) that reduce their radiated power output during a Self Test and therefore these beacons do not transmit a signal that is strong enough to reach the satellites (Note when the antenna is correctly erected these Beacons radiate at full power the same as any other Beacon).

You can check whether your personal locator beacon actually transmits a Self Test burst or not by looking it up in the list of personal locator beacons here

What happens if I set off a false alert by mistake?

Don't panic, as long as it was a genuine mistake and not deliberate you have nothing to worry about, however you must turn off your Personal Locator Beacon and contact the emergency services as quickly as possible to let them know your transmissions are a False Alert.

Deliberate misuse or not notifying the proper authority may incur a severe penalty.

When you call be prepared to provide the following information:

     -The Beacon Unique Identifier Number (UIN) (15 Hex ID printed on the Beacon)
     -The Date, Time and duration of the False Alert
     -The location of the Beacon at the time of the False Alert
     -The cause of the False Alert
     -The primary contact point in the United States for the notification of False Alerts is the United States Air Force Rescue Coordination Center (USAFRCC) the telephone number is 1-800-851-3051.

How do I carry out a Through Satellite Self Test?

In order to carry out a Through Satellite Self Test you must first pre-arrange the Test by filling in the appropriate forms on this web site (see the relevant area for your type of beacon).

You perform the test in the same way as you would for a normal Self Test following the manufacturer's instructions in the user manual for your personal locator beacon. However in addition you must also ensure that:

     -You perform the test out of doors
     -That you have a clear view of the sky, especially to the South (the satellites are typically located in a SE to SW direction at an elevation angle of between       25 to 50 degrees).
     -That the Beacon antenna is vertical (pointing straight up at the sky)
     -Specific details for each type of beacon are provided when you register to test that beacon.

What should I do if I get a Self Test failure?

If you get a Self Test failure, firstly check the instructions in the user manual supplied with your Beacon, make sure you carried out the test correctly and that you have followed any instructions provided. If you are sure your Beacon failed the self test then you should contact the beacon manufacturer or one of their appointed service agents for further advice and instructions.

What if the Through Satellite Self Test Doesn't Work?

Provided that you follow all the instructions on how to carry out the test correctly the test should work. However its important to remember that the Self Test only transmits ONE single burst of data up to the satellites and it is possible in some circumstances for that burst to get corrupted by atmospheric conditions and other anomalies. In an emergency your personal locator beacon transmits a burst up to the satellites every 50 seconds and thus if the first burst does not get through its highly likely that the second or third burst will, however don't worry your beacon will carry on transmitting for at least 24 hours, so even if you are in extreme conditions the message should get through.

If the satellites do not detect the Single Self Test burst from your personal locator beacon, you will receive a Through Satellite Self Test failure message. This may be due to the above noted reasons, or if you do not perform the test within the scheduled time period. If your personal locator beacon responds to its Self Test as specified in your manufacturers manual, it is operating normally.

What does it cost to have the battery replaced?

Personal locator beacons use small but powerful lithium batteries which work well for long periods and under temperature extremes.  The batteries need to be replaced when the shelf life of the battery is exceeded (usually 5-7 years depending on model) or the unit is activated in an emergency situation.  The PLB must be sent to an authorized repair facility and in some cases back to the factory iteself for replacement.  This is required because the battery is replaced and the unit is resealed and tested to be waterproof.  In addition a test is performed on the circuitry to make sure the unit is performing as designed.  The typical cost for this is $150.00.  However, many manufacturers will perform this for free is the PLB was used in an emergency situation and the owner gives permission to use their rescue story as a testimonial.