GPS Beacons?

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Webfoot
Posts: 1759
Joined: November 25th, 2015, 11:06 am
Location: Troutdale

Re: GPS Beacons?

Post by Webfoot » September 12th, 2019, 11:35 am

drm wrote:
September 12th, 2019, 8:30 am
Here's the thing about the ACR - if it is just a basic PLB, how can you know if it is any better at connecting to GPS than the Garmin?
The ACR has a GPS self-test mode that is hard limited to 12 uses per battery. What qualifies as a PASS is not clear to me however; it just flashes a certain sequence, it doesn't provide GPS coordinates on a display or something that could be verified. I think I'll try doing my next one in a canyon or something to see if it still works.

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A. Hugh Jass
Posts: 30
Joined: July 5th, 2019, 7:27 pm

Re: GPS Beacons?

Post by A. Hugh Jass » September 14th, 2019, 7:43 am

drm wrote:
September 12th, 2019, 8:30 am
Here's the thing about the ACR - if it is just a basic PLB, how can you know if it is any better at connecting to GPS than the Garmin?
There is some misunderstanding on how a PLB works. It is not simply reporting your GPS location (a relatively new addition to an PLB). It transmits on a frequency to satellites for use by SAR. First it transmits to a geostationary satellite (GEOSAR). It also transmits the 406MHz signal to polar orbiting satellites (LEOSAR). These LEOSAR satellites will use the transmitting signal to determine (Doppler) your position regardless of GPS data being transmitted (or if no GPS signal is even present!). Finally, when SAR begins to search in the general area, another signal (121.5MHz) is used to "home in" on your location once SAR arrives in your general vicinity. Also, if you registered your device, your emergency contact person is contacted, and perhaps providing more information as to your general location.

In the event that a _real_ life threatening event occurs and an SOS needs to be initiated, the PLB uses 4 methods: 1) GEOSAR detection of 406MHz signal; 2) transmitted GPS location to GEOSAR satllite; 3) LEOSAR Doppler detection of signal; and 4) local SAR team triangulation of 121.5MHz signal.

Both InReach and SPOT use less than 1 watt and only the transmission of your GPS location. And in my experience with InReach it can be off my a mile, literally, and sometimes no signal was sent! Because my ACR ResQLink is only activated when needed, it will transmit to all satellites and local SAR teams for 30 hours at the full 5 watts of power. The use of either InReach or SPOT is a decent decision for safety in the back-country! There is no denying that. However an PLB is the best decision for unmatched reliability and location detection.

Understand this one thing, a device like the ACR ResQLink is designed for the one specific task of getting you rescued, reliably!!!

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RobFromRedland
Posts: 1094
Joined: May 28th, 2008, 10:03 pm

Re: GPS Beacons?

Post by RobFromRedland » September 14th, 2019, 10:19 am

It is interesting to hear other experiences with inReach. I have the "full" unit (GPS plus communicator) and I have two canned messages that I send on all my day hikes. One says I'm starting the hike and the other says I arrived back at my truck and am headed home. It gets sent to my email, my wifes email and a friend of mine. I usually check the location on the map when I get home and the location is always spot on. I've only had one time when I couldn't get a signal out, and once I had a duplicate message which no one was able to explain. Other than those two small issues it has worked exceptionally well for me.

As a GPS tracking device, I think it is terrible, but as a communications device it works well in my experience.
Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: WOW! What a ride! - Hunter S. Thompson

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