Still undecided on which PLB to pickup for the GDR. After probably way too many hours of perusing the net and reading the fine print on the various units out there it's down to either the ResQLink 406 GPS or the Spot 2 Messenger. I found this really helpful article and thought I'd post it here. After reading this I'm thinking that the ResQLink is the better option for not only this trip but for upcoming offshore sailing trips.
"Power and Frequency are two key areas to consider when researching a life saving device. Satellites are thousands of miles away from earth, so your beacon’s signal needs to have enough power to travel that far and be able to go through anything between you and the satellite (trees, weather, out of slot canyons, etc.).
POWER: SPOT is powered by 400 milliWatts while ACR 406 MHz PLBs and EPIRBs use 5 Watts. You would need 12.5 SPOT units to equal the POWER of one ACR PLB or EPIRB! When your signal has to travel 22,000 miles to reach a satellite, you want to make sure you have more than enough power to get it there!
FREQUENCY: The basic principles of frequency are that the lower the frequency, the easier it can penetrate buildings, trees and meteorological activity that appear between the transmitting device (PLB, EPIRB or SPOT) and the receiving device (the satellites). FM radios and TV channels work on a lower frequency which is why they can penetrate buildings and the environment pretty easily. Now think about radar which uses a really high frequency. Radar works by hitting an object and bouncing off, that’s how radar knows where to place an airplane on the radar screen. So the higher the frequency, the less likely it can penetrate things in between, the lower the frequency, the easier it can penetrate. 406 MHz PLBs and EPIRBs use a dedicated frequency set up by the search and rescue community that is in the same range as UHF TV stations. SPOT uses the 1.6GHz frequency which is four times higher in the frequency spectrum. This means SPOT’s frequency is four times less likely to go through an object or weather than the lower 406 MHz frequency.
Considering power, combined with frequency, ACR’s 406 MHz beacon stands head and shoulders above satellite messenger systems like SPOT. ACR has 12.5 times more power and is four times more likely to penetrate objects in between the beacon and the satellite than SPOT.
Redundancies: PLBs and EPIRBs have multiple ways to contact SAR in order to get you rescued. SPOT has one single transmission method. PLBs and EPIRBs can contact SAR via 406 MHz, which locates your beacon using Doppler Shift, it can contact SAR using GPS data and it also has a 121.5 MHz homing frequency so when SAR forces get a few miles away from you, they can home in directly on your beacon and find you faster. SPOT uses GPS only to send its location. If you cannot download GPS, SAR will have no idea where you are!
Coverage: EPIRBs and PLBs use the Cospas-Sarsat satellite system which contains 2 different satellite systems (LEOSAR – Low earth orbiting and GEOSAR – Geostationary). These two systems cover every inch of the planet. SPOT tracker is part of Globalstar and uses the Globalstar (Nasdaq: GSAT) satellite system which only covers a certain percentage of the earth, but has quite a few locations that are undetectable."
Hi,
ReplyDeleteIt's Liron. just had the same discussions with my dad. for both of the reasons you've mentioned I'm prolly gonna go for the ACR as well.
Hey Liron,
ReplyDeleteEnded up picking up my ResQLink 406 a couple weeks ago and it's a tight little unit. Very compact and light. Super quality PLB. Definitely recommend it.
Sorry about the lack of communication the last few weeks. I've been on consults during the week and SAR call over the weekends, unfortunately been more or less living at the hospital. Your titanium El Mariachi decked out with Revelate bags looks like a super solid setup.
I ended up picking up a few more Revelate bags over the last 2 weeks and was contemplating going without the BOB ibex but after a couple long test rides I have been really impressed by the ibex. My climbing time is extended a bit but not by much. I have come to the conclusion that the modest increase in total weight is worth being able to carry the extra gear and in the end shouldn't effect my total daily mileage. Thinking something like 60-70 miles a day to start and then seeing how I feel and going from there. Two weeks and counting!