[pct-l] About my first generation SPOT

[Kathi]

That makes sense. I definitely would not rely on it to save my life 
either. It's nice to know it "might" be able to do that if things go 
south but really for me it is just a nice way for my family to follow 
along. That is if my message goes out!
Thank you for the information.
Kathi

On 10/18/12 10:17 PM, Dan Jacobs wrote:
> On Oct 18, 2012 8:33 PM, "Kathi" <pogo at pctwalker.com> wrote:
>> It was my understanding that the SPOT units do know if the message
>> reached the satellite. Normally when I was testing it and was in poor
>> view of the satellites (between buildings, in my house, etc.) I would
>> get any error message that the satellites were not visible.
> The SPOT device uses two different satellite systems: GPS and
> Globalstar. The device seeing one system does not mean it can use
> both. The SPOT device is a one way communicator: it transmits a very
> short message at very low power "in the blind", meaning it transmits
> the same message more than once so that there is a greater chance of
> the message being received by the satellite. It may still be able to
> successfully transmit its message even without GPS lock, but it cannot
> send a message without a Globalstar satellite receiving it even with
> excellent GPS reception.
>
> According to their manual that I found online, the SPOT unit continues
> to send messages other than 911 for up to 20 minutes, and their
> network tosses out any after the first received attempt
> (http://findmespot.com/en/downloads/SPOT_UsersGuide_2007_10_16.pdf).
> If it was a true two way system where the device was told the message
> was received  there would be no need to continue to transmit for
> twenty minutes and for their system at their data center to toss out
> all of the other received duplicates. If the unit could be told that
> the message was received and to stop sending it, users could have
> their batteries last longer.
>
> Their manual also repeats something kind of vague at least twice that
> I found skimming through it: "That’s why the SPOT Messenger is
> scheduled to automatically send multiple messages in every mode –
> giving you excellent overall reliability" and "It’s normal for some
> messages to be blocked by your environment. Therefore, SPOT
> automatically sends repeat messages, resulting in excellent overall
> reliability." This says to me that the unit sends messages over and
> over in the hopes that just one gets through.
>
> I'm not putting the SPOT device down. I want one, I can't afford one
> right now. I would like my family and friends to have the ability to
> see where I am, what I might be doing. I just won't depend on it to
> save my life. It might help, but I won't put that much trust in any
> one piece of technology.
>
> SPOT is useful, has clearly been shown to be useful, but has also been
> shown to not be as reliable as some folks might have thought.
>
> Dan Jacobs
> Washougal
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