Hey Keith...and all.
Great topic and needs to be back on the radar for everyone.
So, I am shopping for a PLB and found this good discussion on REI...and you know what shopping for a PLB means? Hammer time! Heading out one last time before school...looking for another route between Big Cypress and Everglades WW
Anyway, here's the REI article:
PLBs and Satellite Messengers: How to Choose
While deeply rewarding, backcountry adventures also entail risks that can occasionally prove life threatening—even for the most experienced outdoor enthusiasts.
Technology has come to the rescue with:
Though both are portable transmitters, personal locator beacons and satellite messengers have some important distinctions. This article covers the basics of each.
Personal Locator Beacons
Personal locator beacons are high-powered (typically, 5 watts) devices designed primarily to send out a personalized emergency distress signal. They generally require an open view of the sky to transmit successfully.
PLBs are the land-based equivalents of Emergency Position Indicating Radio Beacons (EPIRBs), a technology that has been in use for decades in marine environments. Over the years, these devices are estimated to have saved more than 33,000 lives.
Important: A Personal Locator Beacon should be activated only in situations of grave and imminent danger, and only as a last resort when all means of self-rescue have been exhausted.
Shop REI's selection of personal locator beacons.
How a PLB Works
PLBs transmit powerful signals at 406 MHz (MegaHertz), an internationally recognized distress frequency monitored in the U.S. by NOAA (National Oceanic and Atmospheric Administration) and the AFRCC (Air Force Rescue Coordination Center).
A PLB communicates with a network of Russian, Canadian, American and French military satellites known as COSPAS-SARSAT (SARSAT is an acronym for "Search and Rescue Satellite Aided Tracking").
After receiving your transmission, these satellites "fix" on your location using a Doppler Shift method and relay your information to the AFRCC where search and rescue procedures begin. If you use a GPS-compatible PLB, you can deliver your GPS coordinates very quickly without having to wait for the satellites to determine your position.
PLB owners must register their device with NOAA. When you do so, NOAA will link your essential personal information to a 15-character code known as a Unique Identifying Number (UIN). When activated, the PLB transmits your UIN to the COSPAS-SARSAT satellites via electronic bursts.
While the electronic bursts provide search-and-rescue units with your location, the UIN tells them personal information such as your name, address, phone number and any medical conditions you may have.
Two Types of PLB Signals
When activated, a PLB sends 2 signals: 406 MHz (which carries the UIN and GPS data to the satellites) and 121.5 MHz, a homing frequency.
If you use a PLB without a GPS, the 406 MHz signal from the satellite will get rescuers to within 2 miles of your position. Then search-and-rescue teams will use a tracking device to home in on the 121.5 MHz frequency. With this type of PLB in the continental U.S., it takes an average of about 45 minutes to alert search-and-rescue teams of your position.
If you use a PLB with a GPS interface, the 406 MHz signal will guide rescuers to an area less than 100 meters from your position. At the same time, they will employ a tracking device to home in on the 121.5 MHz frequency put out by the PLB. When using a GPS-compatible PLB in the continental U.S, it takes only 5 minutes to alert search-and- rescue personnel of your position.
Note: REI carries only models with a GPS interface.
Keep in mind that it's always a good idea to have a visual and/or audible distress signal such as a signal mirror, whistle or strobe light to help catch search and rescue's attention when they get close. Many PLBs include a built-in LED signal light for this purpose.
How Long Will a PLB Transmit?
A PLB comes equipped with a long-lasting lithium battery. This battery remains dormant until you flip the switch to activate the PLB.
By COSPAS-SARSAT regulations:
Cold temperatures will shorten a battery's operating time, and the situations above represent worst-case scenarios. For example, at a temperature of 70°F, these batteries will operate for approximately twice as long as they will at very cold temperatures.
REI currently carries PLB models from ACR Electronics.
No Subscription Fees
Unlike with satellite messengers, you do not have to pay any recurring fees in order to use a PLB. Keep in mind, however, that rescues generally come with significant pricetags.
Much like PLBs, satellite messengers are handheld transmitting devices that are useful in backcountry areas far from reliable cell phone coverage. These user-friendly devices allow you to communicate short text messages and/or your location coordinateswith friends or family back home so you can report on your trip’s status or, in an emergency, send calls for help.
While a handy tool for casual hikers and backpackers, satellite messengers transmit signals that are much less powerful than a PLB signal. They are not intended for serious mountaineering use.
How a Satellite Messenger Works
Satellite messengers are GPS-based devices that rely on either of 2 commercial satellite networks—Iridium or Globalstar—rather than the military network used by PLBs. Emergency calls using either network are routed to the privately run GEOS International Emergency Response Coordination Center headquartered near Houston, Texas.
A subscription fee is required to use a satellite messenger. Each manufacturer offers a variety of usage plan options, usually including duration (yearly, seasonally or monthly) and GPS tracking frequency (with intervals ranging from hours down to a few minutes).
What are the differences between the satellite networks?
Note: Satellite messenger devices are considerably less powerful than PLBs and virtually always require an open view of the sky to transmit successfully.
Each satellite network has its share of fans and detractors relating to their ability to deliver messages 100% of the time. At this point, the jury is still out.
I use both a SPOT and PLB which in mandatory for WaterTribe events that I enter.
The SPOT is solely used for tracking purpose so that my loved ones know where I’m at when out on camping trips. It also has a SPOT Adventures webpage that I use to post some of my trips (http://www.findmespot.com/spotadventures/index.php/public_profile?profileid=73828 ). I know that many SPOT users have reported dropped messages and worst case dropped Help messages. This is why I will not rely on SPOT as a safety device. You have a onetime fee for the device plus a yearly subscription is $ 178.05 that includes optional tracking.
Have had my SPOT since 2011 with not issues. I keep mine in a small clear waterproof bag with some dessicant packets.
I also carry an Ocean Signal PLB which is the smallest PLB on the market today. When you registered with NOAA you get your own user account that you can change/update your info on. This comes in handy when you don’t use the same vessel for all your trips. This will be my go to device if sh*t hits the fan while in the Glades. Anything can go wrong but a PLB brings peace of mind.
SPOT currently has a 50% off deal.
Just looked at my EPIRB/PLB and realized that the battery expiration date has passed. NOAA requires new batteries every 5 years.
Went online to get the battery. Not so easy my friend...
Can't do it yourself, you have to send to to a service center. $160 +shipping both ways...
Probably cheaper to buy a new one!
So basically when you look at the price of a PLB, amortize it over a 5 year life!