Seeking info on Personal Locator Beacons (PLB)

HikingMano

HikingMano

Joined
Sep 2, 2008
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I want to pick up a PLB this year and am now in the research stage of the purchase. Can anyone knowledgeable advise me on what specific features or companies I should seek out and why? Recommendations on specific models/companies are fine, but please provide info on what advantage that model has over others. I won't say price is a non-issue, but I value reliability over price.

Feel free to share any relevant and underlying info (how a PLB works, why it works the way it works, terrain tips, ease of sending in for battery replacement, tips on registration or account service etc). I'm still learning quite a bit about it all, so any info is welcome.

One more note: I want a PLB, not a SPOT.

Thanks in advance.
 
are you looking for something like an avalanche transponder beacon? I see you say you don't want a SPOT, which I think are pretty nice especially the newer ones you can connect to your phone to text and email but anyways off subject.
I do a lot of mountaineering and work as a guide and I also do a bunch of backcountry snowboarding and I have a RECCO installed in my jacket and also carry a separate MAMMUT PULSE BARRYVOX transponder beacon. most places recommend carrying two beacons incase one stops working for whatever reason & also to have one that can be used to locate other signals. many places with avalanche zones only allow you out if you have the beacon and locator and are in a group of 2 or more so that you can locate and help your buddies before rescue can get there. I also have my SPOT on me when in the back country more for remembering my routes and being able to text and stuff when theres no cell service.
im not sure if the avalanche type beacons are what your looking for but, the mammut brand has a couple different ones that are rated pretty high in all reviews. it isn't just a locator but it can also be switched to search mode and has some amazing features like being able to sence tiny movements to tell if the person is still alive, it can handle multiple signals at once. it automatically keeps itself on transmit if your not activally searching or checking signals of your buddys in your group so if you get in trouble it will always be transmitting and not recieveing signals. luckily I have never had to use it in a real situation but ive used it just to try it out and learn all the features and also use it a lot to check signals in our group and to see where people are if we get separated and its always worked very good. I think when I bought the mammut it was right around 400$ the recco came in my jacket and my jacket was like 600$ but you buy no means have to spend that much. ive seen some jackets that are only a couple hundred that come with the beacons in them and ive seen some locators/beacons at places like REI for less then 200$, it really depends on weather you want just a basic beacon that only transmits a signal, or you want a transmitter and receiver all in one. the transmitter only can be bought for pretty cheap I think.
 
My current understanding is that the 406 MHz emitting beacons (EPIRB for marine use, ELT for aviation, PLB for personal use) provide a stronger signal that would be more reliable under conditions where terrain or weather could hamper a signal reaching satellites (5W 406 MHz for the ACR ResQLink PLB vs 0.4W 1610 MHz for the SPOT. I haven't worked out yet if it's the higher wattage, lower frequency, or combination of both that makes it "stronger"). And while having a unit with GPS capability and clear view of the sky/satellite helps pinpoint location more quickly/accurately beyond doppler triangulation, 406 MHz emitting radiobeacons don't require a clear view of the sky to get through. The 406 MHz digital signal can get rescuers within 5km, and with a unit like the ACR ResQLink, the weaker 121.5 MHz homing signal can be utilized by air-craft or ground crews to zero in. If you can get the GPS coordinates sent out, even better; accuracy is 15m but because of the limitations of transmitting the information to the satellite, GPS coordinates will put responders within 125m. Furthermore, the PLBs operate on the same COSPAS-SARSAT system as EPIRBs and ELTs, vs. the Globalstar commercial satellite system that SPOT uses. COSPAS-SARSAT covers the entire globe, apparently, and is international and government/non-profit/humanitarian. Globalstar is profit-driven, and apparently has gaps in coverage (poles, south africa, should be fixed this year though) and there seem to be reliability issues. I would rather put my trust in COSPAS-SARSAT rather than Globalstar. There is some nuance in response time too, from activation of signal, but I haven't quite got all that straight yet.

So basically, I think PLBs provide a more reliable signal to a more reliable satellite network, and is therefore more likely to get you rescued.

In addition, I think the cost of the PLB unit (I've had my eye on the ACR ResQLink+ = $289 retail from REI) + Registration/Service (Free to use COSPAS-SARSAT, $40 or $60 yearly if you want confirmation of self-tests from ACR ) is cheaper over the long term vs. the SPOT ($150 retail REI) + annual subscription ($100 per year). To clarify, you can buy the ACR and do a limited number of self-tests (60), but this just lets you know that the unit is functioning and transmitting, not that the entire signaling process ran to completion. If you want that added security, you have to buy the subscription, which gets you email or text confirmation that a signal was sent.

Lastly, while SPOT does offer more options in terms of tracking and communicating with loved ones at home, with a $60 subscription purchase from ACR (still cheaper than SPOT) I can basically send the same "I'm ok" messages via a PLB through a self-test. So if I'm running late, or sprained an ankle or something but can still self-rescue and prevent paying for an unnecessary SAR call-out, I can just do a self-test to let loved ones know I'm OK even though I'm over-due. One note, I think this messaging service only applies to the Americas and Pacific and Atlantic oceans, which is fine with me. Anyway, aside from the contact-with-loved-ones, I'd want the subscription just to confirm that the entire system -- from signal to alert/receipt -- works before trips (annual subscription gets you 220 self-tests). I don't really want or need the tracking features SPOT offers. I just want something that will signal reliably if I am ever in a truly bad situation where self-rescue isn't possible. An argument can be made for the bread-crumbs approach to rescue, but I would rather have a strong and reliable signal when I actually need it. And if I am capable and have to move, a PLB like the ACR transmits for up to 30 hours in "typical conditions", a burst every 50s.

Plus, I don't know how accurate this is, but I have this impression that the PLBs are constructed to be much more robust than SPOT or other such SENDs.


Anyway, I'm still digging into the nitty gritty of it all, but this is more or less what I've gleaned that's led me to prefer a 406 MHz emitting PLB over a SEND like SPOT. I'm sure there's stuff I've missed or fumbled over, but I've been trying to form a complete and unbiased picture from various sources. And of course, take this all with a grain of salt, as I don't have any first-hand experience, and I have come across some seemingly compelling arguments for SENDs. Some interesting stuff by Doug Ritter here. Judging by his take, the 406 beacons on COSPAS-SARSAT are functionally superior, at least for the time being, but the consumer market is pushing things towards SENDs.
 
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Did a quick sketch of cost projections with the various units. For ease, I just went with retail prices listed on REI and stated subscription costs. Remember, you don't NEED a subscription to use the ACR ResQLink to signal rescue through COSPAS-SARSAT, registration with NOAA is free. But, I would get the top level subscription myself because it would allow me to send my self-test confirmations to 5 other people, so I can use it as an "I'm ok" message to loved ones. Plus, I'd simply want to know that the entire system is in good working order before setting out on trips.

With that in mind, you can see that although you put up a little more money up front going with the ACR + top tier subscription, you ultimately save a little money vs. the SPOT Connect (best value of SENDs included here) beginning at 4 years. At 5 years you save $56. Is it enough to be worthwhile in light of the features/capabilities you want? That's up to you. I think it's a good deal myself to save a little money while getting the "better" (IMO) rescue device. Stacking odds in my favor for survival is my primary concern; if I valued tracking and messenger functions more, I'd be more inclined to go the SEND route.

The most cost effective route would be the ACR without a subscription, where you can only do unit tests to check that it's transmitting (but you don't get confirmation of the system working that you'd get in a "through-the-system" test).

Chart_zps71c97348.png


I can imagine there are some situations where the tracking ability of the SENDs would be useful. Perhaps you lose or can't reach your PLB somehow (Aaron Ralston type situation, perhaps), now you're out of luck because of the usage model. The SEND would at least have your bread-crumbs for responders to follow when you don't show up at home on schedule or someone at home notices you haven't made any progress. I can't really think of any likely situation other than that where it'd have an advantage. If I'm alive and have it on me, I should be able to activate it. If I'm unable to do that, I'm either dead or soon to be dead because I've been caught in an avalanche and will suffocate unless help is nearby (or some similar bad situation where you simply run out of time).
 
As always, thorough research intelligently and simply presented. Thanks. :)
 
The biggest thing is to register it. I've been involved on the fringes of the mechanics of how the system works and the biggest thing is that you need to register it so that it quickly becomes a name and not just a beacon number. Also getting a beacon with GPS really helps in the efforts. Having 2 or 3 sat passes on a stationary beacon ups the ante vice over a beacon that is moving around. The other thing, is once you activate it, keep it on. Don't think that turning it off to conserve batteries is a good thing. Constant broadcast is the key indicator of trouble.
 
Right, definitely register is the gist of what I got, it really helps the rescue process. Thanks for the reinforcement and other tips, swonut :thumbup:

RWT and Taldesta, happy to share the little I've learned so far :thumbup: I was seeking info and not anticipating providing much, so sorry if things weren't very clear. I've had to get used to quite a few new acronyms (GEOSARs, LEOSARs, LUTs, AFRCC, etc.), let alone system details, haha :)
 
very useful thread.
Full disclosure, I work for a PLB maker (we made the first mini PLBs a number of years ago), and as a corporation are closely invloved with the regulatory bodies that determine what can and can not be included in PLBs.

As a PLB maker we decided to not have subscription services as part of our PLBs, because (among other reasons), the confusion that exists among users between what the privatly operated SEND services offer, their strengths, limitations, and those of PLBs utilizing official Search and Rescue notification services coordinated through NOAA, Cospas Sarsat, and dozens of other goverment agencies around the world.

Bottom line, if distress notifcation is the issue, get a PLB.
They not only have the lowest cost of ownership (in truth under $250!! if you buy right divided by the 6 years the batteries are typically rated for), but they are the real deal, as (in N America for example), you register with NOAA, or The Canadian goverment's Beacon Registry dept.
Here are some resources worthy of taking a peek at as part of your research.
Bill

http://cospas-sarsat.org/index.php
http://www.sarsat.noaa.gov/beacon.html
https://www.cbr-rcb.ca/cbr/presentation/other_autre/index.php?lang=en
http://www.fastfindplb.com/us/
 
Thanks for the disclosure, Beastwood :thumbup:

Beastwood said:
[...] Bottom line, if distress notifcation is the issue, get a PLB. [...]
Click to expand...

:thumbup:

Can you tell us more about why McMurdo decided not to include subscription services as part of your FastFind PLB offering, aside from the emphasizing the difference between SENDs and PLBs?

______________________________________________________________

Some side notes:

-Equipped to Survive field testing of early PLBs, with lots of good background info.

-This ITU-R report has a quick little overview of the distress alert system and doppler localization.

-I've been looking into why a 406 MHz digital signal is said to be "stronger" vs. the higher UHF 1.610 GHz signal, as in the physical reason. Interactions with various objects (as related to the outdoors: rock, water vapor and other gases in atmosphere, etc) can be complex it seems. But in general, as an eletromagnetic wave, the lower frequency will penetrate the atmosphere better and pass through tree cover better because the waves won't get absorbed/reflected/diffracted as easily as the smaller wavelengths of the higher frequencies. It seems that a signal is particularly degraded by absorption into atmospheric moisture, and degradation is proportional to frequency. So I guess the difference between 406 MHz and 1610 MHz is significant enough to give you better line-of-sight penetration through to the satellites. Big hills or canyon walls can still block them (but I think it's possible for the 406 MHz signal to be reflected out). And, remember, the 121.5 MHz analog homing signal is picked up only by ground/air equipment, not satellites.

Also, a cool note for the future:
COSPAS-SARSAT currently consists of Search and Rescue signal repeaters and processors on 8 geosynchronous earth orbit satellites (labeled GEOSAR satellites) and 6 low earth orbit satellites (LEOSAR satellites). Apparently a new network is going into place that should facilitate faster rescues and possibly even two-way information exchange through Europe's Galileo network (cool!).

Wikipedia quote, but a fine launch point for further investigation, should you wish:
Wikipedia said:
Supporters of the Cospas-Sarsat system are preparing to demonstrate and evaluate a new capability called MEOSAR (Medium Earth Orbit Search and Rescue satellites), consisting of SAR transponders aboard navigation satellites of Europe, Russia and the United States. In its current (project) form, the U.S. space-segment component is being called the Distress Alerting Satellite System (DASS) by NASA.[12] MEOSAR will consist of SAR transponders aboard Europe's Galileo constellation, Russian Glonass spacecraft (Glonass-K1 having been launched on 26 February 2011), and the U.S. GPS satellite constellation. MEOSAR assets will report signals from Cospas-Sarsat search and rescue beacons in the 406.0–406.1 MHz band.[13] MEOSAR satellites will be able to provide near-instantaneous detection, identification, and location determination of 406 MHz beacons. The beacon can transmit coordinates of its position encoded in the alert message (if the position information is available from an on-board GNSS receiver or another source such as a ship's navigation sensors). Or the position can be determined independently by the receiving LUT by analyzing the frequency-difference-of-arrival (related to Doppler-induced variations) and/or the time-difference-of-arrival. It is planned that the MEOSAR system will be able to download information back to the distress radiobeacon by encoding "Return Link Service" messages into the Galileo navigation data stream.
Click to expand...

DASS
Galileo


ETA:
I decided I'm going to go with the regular ACR ResQLink over the + version. I don't think the increase in weight and bulk is worth it for my uses (and it's only useful if you have it on you). If carrying it around water or on a plane, I'll just make sure to dummy cord it to myself. Otherwise, in regular carry, it'll be secure on my person in a pouch or pocket. I'd probably have it dummy corded even then.

Still haven't decided on the subscription. I think it'd be handy and comforting for both the "I'm ok/delayed" messaging capability and testing it before big trips. I'm thinking I could make the cheaper subscription work for me through use of automatic email forwarding (don't really need the other stuff the top subscription offers).



ETA 2:
Bought the ResQLink a few days ago and registered with NOAA. Took advantage of a $50 rebate promotion ACR has going on now through August. The 406Link subscription site is being worked on right now, but I'll sign up for the $40 annual basic subscription once it's back up and running. I'm going to have it sent to my girlfriend's email, and I will have to work out how to filter the messages such that it's automatically forwarded to any one else we'd like to send "I'm OK" test confirmation messages to (in the event my GF is with me and others are expecting us back at a certain time).

The unit is tiny! No excuse to not carry it everywhere (pictured with some new shoes):

IMG_2738_zps5d914fd1.jpg
 
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