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Satellite Rescue Beacons:
    Keeping in Touch and Calling for Help  (10/08) 

    by Douglas Dixon

Personal Locator Beacons (PLBs)  - ACR TerraFix and MicroFix PLBs
SPOT Satellite Messenger

See also Satellite Phones - Iridium, Thuraya, Inmarsat, Globalstar

See my article in the Oct. 2008 issue of Condé Nast Traveler for summaries of these products
    Trip Tech: Far and Away -

Personal Locator Beacons (PLBs)

While you can use a satellite phone to keep in touch when travelling in remote areas, calling to chat does defeat the whole idea of getting away. But if you're concerned about needing to be able to call for help in an emergency, you can carry a Personal Locator Beacon (PLB) instead. PLBs have only one function -- to broadcast a distress signal that will activate the international Search and Rescue (SAR) system to respond to a life-threatening emergency.

PLBs were authorized for nationwide use in the United States in 2003. They use the same Cospas-Sarsat international satellite system for search and rescue used for marine and aircraft distress beacons, which has provided assistance in rescuing more than 22,000 people in over 5,000 incidents since 1982 (


Alerts received from these devices are then transmitted to the mission control center for the associated area, which then coordinates through the associated national authorities to deploys aeronautical and maritime search and rescue. In the United States, the system is operated by the National Oceanic and Atmospheric Administration (NOAA), which then dispatches to Air Force and Coast Guard rescue coordination centers (

The SAR satellites can triangulate your location within about 2 to 3 miles to define the initial search area. Newer PLBs add integrated GPS to pinpoint your location down to around 100 meters. PLBs also include a low-power homing beacon to guide rescue forces directly to your location.

PLBs typically are rugged and waterproof, and transmit the signal for 20 to 40 hours. They can work in harsh weather conditions down to -40 C, and with restricted visibility to the sky, such as in canyons and under heavy tree canopies.

PLBs are available from outdoor and sporting supply retailers for around $500 to $700, including Sports Authority, Dick's, R.E.I., L.L. Bean, and Orvis. You then register the device with your emergency contact information. You also can rent PLBs from a few sources including for around $60 to $70 a week. There are no additional costs or annual subscription fees. The batteries typically have a 5 year replacement cycle (or up to 11 years in storage).

You then can just pack the PLB along when you travel. Just don't press the big red button by accident -- unless you have a real emergency and need to call out the rescue helicopters.

The most commonly available units in the U.S. are the TerraFix and MicroFix from ACR Electronics ( 

The ACR TerraFix (shown) is available for around $499, or $599 with GPS. 

The newer ACR MicroFix is 35% smaller and 25% lighter (9.98 vs. 13.6 ounces), with GPS, but does not float like the TerraFix. It's available for around $699.


Related Search and Rescue Equipment:
    ELTs (Emergency Locator Transmitters) - aircraft signal distress
    EPIRBs (Emergency Position-Indicating Radio Beacons) - maritime signal distress
    PLBs (Personal Locator Beacons) - personal use

         Find the ACR TerraFix and MicroFix on


SPOT Satellite Messenger

The SPOT Satellite Messenger is designed as a lower-cost variant of a Personal Locator Beacon. You can use it to call for emergency help, or to send update messages with your GPS location ( 
It's a fun and useful product at the price for some get-aways, but consider stepping up to a PLB when you are going seriously remote.

The SPOT has three buttons to signal your status while travelling. Press the 911 button to call out emergency search and rescue like a PLB. Press the OK button to check in and reassure your friends and family that you are still on the map. Or press the Help button to ask for non-emergency assistance (such as an early pick-up) without calling out international search and rescue. The OK and Help notifications are sent by text message and/or e-mail to the list of contacts that you registered at the product website, and include your GPS coordinates and a link to the location on Google Maps.


The 911 distress message is routed to the appropriate emergency responders based on your location and personal information. The message is sent every five minutes until cancelled to help track your location if you are moving. The Help message will be sent even if the SPOT unit cannot establish a GPS fix, and is transmitted every five minutes for one hour, or until cancelled.

The basic SPOT device costs $149, and requires an annual service plan of $99 a year to forward messages. You also can add a $49 per year Tracking option that updates your location ever 10 minutes on a shared Google Maps website so others can track your progress.

    Tracking on Google Maps

Plus, SPOT offers a $7.95 per year GEOS Search and Rescue option though the GEOS Alliance service that handles the 911 messages ( GEOS then manages the rescue process, using private resources if needed when official emergency services are not able to respond fast enough. The option also includes up to $100,000 per year of coverage ($50,000 per incident) for costs associated with private or public rescue efforts.

Read the coverage conditions for specific details: It does not apply if your emergency was due to a lack of common sense, it does not cover extraction of your dead body, and it only covers one specific person -- add $7.95 more per year to cover each additional family member.

The SPOT unit itself is palm-size and relatively lightweight (7.4 oz.), and is designed to be drop-resistant, waterproof, and to float. The minimal interface has LED lights that indicate that it's active and sending a message, but since the SPOT is a transmit-only device there's no confirmation that the message got through.

My SPOT worked fine in most circumstances. I received text and e-mail messages within 5 to 10 minutes of pressing the buttons, and the tracking mode missed at most one message each hour during an overnight test placed in a window with a limited view of the sky. But the SPOT was less successful while travelling -- getting 2 to 4 of the 6 messages though per hour when clipped to my bag during a hike through light woods and open fields, or when clipped to my car's sun visor during a tour up and down the Delaware River.

One concern is that SPOT is a subsidiary of Globalstar. The company reports that problems with its degrading satellite system have "essentially no affect on the reliability of Simplex (one-way) data network, [and] therefore products like the SPOT Satellite Messenger are affordable and highly reliable."

Globalstar Simplex Coverage Map -

         Find the SPOT Satellite Messenger on