SPOT should be ashamed

[Pat Russell]

Why, oh why, after recognizing the need to advance the state of the
art of Search and Rescue, after going to all the trouble and expense
of designing a clever low-cost device that can communicate with two
separate satellite services and the 911 infrastructure, after going to
all the trouble of determining an accurate fix in three dimensions,
WHY DOES IT REPORT ONLY TWO OF THEM?

[Sarah Anderson[_2_]]

Pat Russell wrote:
> Why, oh why, after recognizing the need to advance the state of the
> art of Search and Rescue, after going to all the trouble and expense
> of designing a clever low-cost device that can communicate with two
> separate satellite services and the 911 infrastructure, after going to
> all the trouble of determining an accurate fix in three dimensions,
> WHY DOES IT REPORT ONLY TWO OF THEM?

Because there's two kinds of people, pilots and ... no, I won't
go there.

Because there's 10 kinds of people, those who understand binary
and those who don't

/ticheek

Sarah

[5Z]

On Apr 30, 4:52 pm, Pat Russell > wrote:
> WHY DOES IT REPORT ONLY TWO OF THEM?

Because this is a rescue device.

When is it ever necessary to rescue someone floating in mid air?

SPOT was designed for HIKERS, and I'm sure they think it's perfect. I
carry mine in the car when driving between Denver and Colorado
Springs, as mobile phone coverage is spotty if you get more than a few
miles from I-25. If I need help while soaring, it will be on the
ground.

If it was designed for pilots, it would cost at least 3 (10?) times as
much and do half of what this one does... :-(

But there's always hope that a more pilot friendly device can be built
on top of this one by adding a few more buttons or at least changing
the firmware. They will likely charge a bit more for the service as
we'd like to have a better chance of our live track getting received,
so it will need to send more position reports, thus cluttering the
bandwidth, etc...

-Tom

[Marc Ramsey[_2_]]

5Z wrote:
> But there's always hope that a more pilot friendly device can be built
> on top of this one by adding a few more buttons or at least changing
> the firmware. They will likely charge a bit more for the service as
> we'd like to have a better chance of our live track getting received,
> so it will need to send more position reports, thus cluttering the
> bandwidth, etc...

I looked at implementing a SPOT-like device using this technology years
before SPOT was announced, the main problem (aside from being transmit
only) is that data messages to the Globalstar network contain only a
small number of bits (56?). After one encodes latitude and longitude at
a useful resolution, about all that is left is a few bits to encode
"OK", "HELP", etc. I suspect an upgrade would require more satellites,
something which Globalstar may not be able to afford...

Marc

[D.Rizzato]

I phoned England where the provider of the 911 is located
asking to test my SPOT,s 911 I was told that there are not willing and able
to
have the system tested ! So if I can not test the 911
like a ELT what is the use, all it provides me with is a false security.
By the way just try the SPOT warranty system, make sure you
have your credit card on hand because you pay for everything
even if it fails when you take it out of the box







"Marc Ramsey" > wrote in message
. ..
> 5Z wrote:
>> But there's always hope that a more pilot friendly device can be built
>> on top of this one by adding a few more buttons or at least changing
>> the firmware. They will likely charge a bit more for the service as
>> we'd like to have a better chance of our live track getting received,
>> so it will need to send more position reports, thus cluttering the
>> bandwidth, etc...
>
> I looked at implementing a SPOT-like device using this technology years
> before SPOT was announced, the main problem (aside from being transmit
> only) is that data messages to the Globalstar network contain only a small
> number of bits (56?). After one encodes latitude and longitude at a
> useful resolution, about all that is left is a few bits to encode "OK",
> "HELP", etc. I suspect an upgrade would require more satellites,
> something which Globalstar may not be able to afford...
>
> Marc

[Ron Lee[_2_]]

Pat Russell > wrote:

>Why, oh why, after recognizing the need to advance the state of the
>art of Search and Rescue, after going to all the trouble and expense
>of designing a clever low-cost device that can communicate with two
>separate satellite services and the 911 infrastructure, after going to
>all the trouble of determining an accurate fix in three dimensions,
>WHY DOES IT REPORT ONLY TWO OF THEM?

Got to tell you that I would be happy to report my Lat/long to
SAR assets. Anyone local would know if the elevation is 100' or
13,000' MSL.

Think of the number of folks who would be saved with something
like Spot.

If you want altitude look into APRS. Here is some info:

http://tinyurl.com/624vv6

Ron Lee

[JS]

Perhaps I'm missing the point here?
This thing cost $150 US. What aviation instruments can you get for
"a buck fifty"? A magnetic compass costs more.
And as Tom put it, if S+R have your Lat and Lon they will likely look
for you on the ground, whatever the elevation.
Since the demise of the dial-up modem, everyone has forgotten that
bandwidth costs money.
Jim

On Apr 30, 8:14 pm, (Ron Lee) wrote:
> Pat Russell > wrote:
> >Why, oh why, after recognizing the need to advance the state of the
> >art of Search and Rescue, after going to all the trouble and expense
> >of designing a clever low-cost device that can communicate with two
> >separate satellite services and the 911 infrastructure, after going to
> >all the trouble of determining an accurate fix in three dimensions,
> >WHY DOES IT REPORT ONLY TWO OF THEM?
>

[noel.wade]

On Apr 30, 4:47*pm, Sarah Anderson > wrote:
> Because there's two kinds of people, pilots and ... no, I won't
> go there.
>
> Because there's 10 kinds of people, those who understand binary
> and those who don't
>
> /ticheek
>
> Sarah


OK, this is off-topic and probably going to come out sounding all
wrong; but Sarah, whoever you are, I love you!

Pilot... Check.
Geek... Check.
Woman... Check (or at least a safe bet, given the name *grin*)

...What a gem! If you have a significant other, tell him/her that I'm
very jealous. :-)

--Noel

[Happy Trails]

On Wed, 30 Apr 2008 18:52:31 -0400, Pat Russell
> wrote:
>all the trouble of determining an accurate fix in three dimensions,

Is there somewhere in the specifications where it actually says this,
or are you just making an assumption here?

As far as I can tell, it can fulfill all it claims to by determining
lat & lon only. Did you mistakenly think you were buying an accurate
altimeter or something?

[5Z]

On Apr 30, 7:56 pm, "D.Rizzato" > wrote:
> I phoned England where the provider of the 911 is located
> asking to test my SPOT,s 911 I was told that there are not willing and able
> to
> have the system tested ! So if I can not test the 911
> like a ELT what is the use, all it provides me with is a false security.

Except for a few bits in the message itself, there is no difference
between 911, HELP, or OK. You can test it to your heart's content by
sending either of the latter messages to yourself or friends.

I don't know about the UK, but in the US, dialing 911 from my house
just to see if it works is not permitted. So I have to trust that if
I get a dial tone, I'll be able to reach 911.

It's possible that the connection between the SPOT message handling
center and their 911 center is down, but I assume the message handling
system will keep trying until a human acknowledges the request. It's
also possible the 911 button on your unit is broken, but then the LED
won't flash, and you'll know it. If the LED flashes, and if a recent
OK message went out, you can be fairly confident that the 911 will go
out as well.

As for customer support, I've had excellent response with general and
technical questions. Every business, no matter how good, will
occasionally **** someone off and with the internet, we find out about
it much more often that in the past.

Bottom line, this device is damned inexpensive for what it provides.

-Tom

[[email protected]]

On Apr 30, 6:30*pm, Marc Ramsey > wrote:
> 5Z wrote:
> > But there's always hope that a more pilot friendly device can be built
> > on top of this one by adding a few more buttons or at least changing
> > the firmware. *They will likely charge a bit more for the service as
> > we'd like to have a better chance of our live track getting received,
> > so it will need to send more position reports, thus cluttering the
> > bandwidth, etc...
>
> I looked at implementing a SPOT-like device using this technology years
> before SPOT was announced, the main problem (aside from being transmit
> only) is that data messages to the Globalstar network contain only a
> small number of bits (56?). *After one encodes latitude and longitude at
> a useful resolution, about all that is left is a few bits to encode
> "OK", "HELP", etc. *I suspect an upgrade would require more satellites,
> something which Globalstar may not be able to afford...
>
> Marc

dont you just need 1 bit to encode "okay" vs "/okay"
alright, 2 bits if you want "okay", "/okay", "fallen can't get up"

[Darryl Ramm]

On May 1, 11:59 am, Happy Trails > wrote:
> On Wed, 30 Apr 2008 18:52:31 -0400, Pat Russell
>
> > wrote:
> >all the trouble of determining an accurate fix in three dimensions,
>
> Is there somewhere in the specifications where it actually says this,
> or are you just making an assumption here?
>
> As far as I can tell, it can fulfill all it claims to by determining
> lat & lon only. Did you mistakenly think you were buying an accurate
> altimeter or something?

The GPS chipset used calculates location in 3D, like which GPS chipset
would'nt. The SPOT device does not send that over the Globalstar link
for reasons noted earlier (message length, device intended for
hikers). The specifications on GPS chipsets used in SPOT and the
Global star message formats are all public information. Lots of
information at http://www.axonn.com.

As for being ashamed, wrong! It would be great to have altitude data,
but Globalstar should be proud of their little SPOT child for leaving
home and doing well the first year away.

If people really want a 3D capable unit, designed for aviation etc.,
they are available on the Iridium network. Your imagination is only
limited by your check book.

Darryl

[Eric Greenwell]

5Z wrote:

> Except for a few bits in the message itself, there is no difference
> between 911, HELP, or OK. You can test it to your heart's content by
> sending either of the latter messages to yourself or friends.
>
> I don't know about the UK, but in the US, dialing 911 from my house
> just to see if it works is not permitted. So I have to trust that if
> I get a dial tone, I'll be able to reach 911.

Nor do you turn on your ELT and wait for search and rescue to show up,
to see if it "works".

> It's possible that the connection between the SPOT message handling
> center and their 911 center is down, but I assume the message handling
> system will keep trying until a human acknowledges the request. It's
> also possible the 911 button on your unit is broken, but then the LED
> won't flash, and you'll know it. If the LED flashes, and if a recent
> OK message went out, you can be fairly confident that the 911 will go
> out as well.

If you don't trust their 911 service, make the "send help" button your
personal 911, with a friend/wife/employee with email or a cell phone
ready to call search and rescue. Not as elegant, but you can "test" it.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org