Mystery PLB signal finally figured out...

[Brian in SLC]

I know PLBs, SPOTS, etc have been discussed a bit here.

Amusing, sorta.

Cheers,

-Brian in SLC

http://www.wildsnow.com/2323/plb-rescue-beacon-acr/

The Problem With PLBs, ACR, Spot Messenger, Etc.
By Lou
Update, March 3. Wow. Rocky Mountain Rescue Group (RMRG) persevered and solved the mystery of the ghost personal locator beacon (PLB) that

[RedMan]

That is the problem with PLBs. They will work without registration.
The SPOT won't work if you dont go on line and complete the resistration process so they have alternative contacts to verify the nature of the
potential problem.

I think PLB's are old hat and should be discontinued.

The "people will stop caring" argument is disconcerting but the same arguments was made about 911. Everyone said its to simple and too many
children will dial it clogging the lines and lonley drunks will tie up all the
resources. That was decades ago. I think 911 was a good idea.

[UtahAdventureGuide]

Was his name Aron Ralston by chance?

[Ryebrye]

Aron Ralston would have ruined the PLB the first time he tried to turn it on using a dull pocket knife and his rusty claw.

[Ryebrye]

That is the problem with PLBs. They will work without registration.
The SPOT won't work if you dont go on line and complete the resistration process so they have alternative contacts to verify the nature of the
potential problem.

I think PLB's are old hat and should be discontinued.

If my life were on the line, I would much rather have a PLB. PLB's use COSPAS-SARSATs and SPOT uses communication sats. PLB's also transmit a homing frequency at 121.5 MHz and some at 406MHz. PLB's can send a signal out that can be detected even if they can't get a GPS fix that can get rescuers within 3 miles and then they can use the homing frequency to find you.

Now, as far as usability goes, the SPOT is more useful on a normal basis because you can use it for non-emergency situations. Unless you are the worlds most unlucky person, a SPOT should get a whole lot more use in its lifetime than a PLB...

So as far as which one I would rather have out hiking with me, it'd probably be a SPOT - but if I was somehow trapped and a genie came out and said "I grant you one wish, but the wish must be to get some kind of emergency transmitter, which will you have: a SPOT or a PLB?" I'd pick the PLB.

A GOOD PLB (one that includes GPS) runs between $350 to $750 with no annual fees. a SPOT runs around $100 with $100 a year (and $50 more if you want their tracking feature turned on).

I can see a case for both, but SPOTs don't completely PLBs and the consumer has to decide which they would rather have - but PLB's aren't going to go away any time soon.

[RedMan]

If my life were on the line, I would much rather have a PLB. PLB's use COSPAS-SARSATs and SPOT uses communication sats.

My math says thats a bad bet.

According to wiki:
The space segment of the Cospas-Sarsat system currently consists of SAR processors aboard 4 geosynchronous satellites called GEOSARs and 6 low-earth polar orbit satellites called LEOSARs. BTW these are 1970's technolgy, launched in the 80s. They are really old and I know satellites do not last forever. According to NOAA two have been decomissioned and two are having internittent problems leaving only 2 fully functioning leosars and one of the GEOSARS is under evaluation (it can't be trusted). So that leaves 6 functioning birds covering the whole planet.


In February 2000 Globalstar launched the last of 52 satellites

[RedMan]

BTW, in order to make use of the PLB homing frequency you need equipment and personel trained to use it. Many Utah and Colorado counties do not have either.

No SPOT does not have this homing beacon capability but the Ralston lesson is do not travel alone. If you are in a team then chances are very good that at least someone in your party can get to a location with a clear shot of the sky and use SPOT.

[Ryebrye]

The PLB program is completely dependent on funding from multiple governments. I can tell you that is a recipe for disaster, if one of them balks at the funding then things get massivly delayed.

This isn't quite true. The signals come from the satellites to the fixed operations centers. If you are in the US and have a US-registered 406-Mhz PLB, the only country involved is the USA.

Given my direct (daily) experience with government funding I will predict right now that the PLB is in jeopardy of vanishing.

No, it wont.

There is a commercial alternative now, the SPOT. The simple fact that replacement sats for the dead birds have not been launched tells me the program is slowly being killed. I know a dying program when I see one, I do this for a living.

If you continued to read the wikipedia article, you would see that they are working to add 406Mhz response time to the GPS satellite constellation and they are working to add 2-way communication back to devices (obviously future devices) using the MEOSAR system:

[quote=part of the wikipedia article you didn't read]
Supporters of the Cospas-Sarsat system are working to add a new capability called MEOSAR (Medium Earth Orbit Search and Rescue satellites.) In its current (project) form, it is being called the Distress Alerting Satellite System (DASS) by NASA.[7] This system will put SAR processors aboard the GPS satellite constellation and the Galileo positioning system constellation. MEOSAR satellites will be able to provide near-instantaneous detection, identification, receipt of encoded position, and determination of Doppler triangulated position of 406 MHz beacons (exclusively.) MEOSAR assets will report signals from Cospas-Sarsat search and rescue beacons in the 406.0

[RedMan]

[quote=Ryebrye]

The PLB program is completely dependent on funding from multiple governments. I can tell you that is a recipe for disaster, if one of them balks at the funding then things get massivly delayed.

This isn't quite true. The signals come from the satellites to the fixed operations centers. If you are in the US and have a US-registered 406-Mhz PLB, the only country involved is the USA.

Given my direct (daily) experience with government funding I will predict right now that the PLB is in jeopardy of vanishing.

No, it wont.

There is a commercial alternative now, the SPOT. The simple fact that replacement sats for the dead birds have not been launched tells me the program is slowly being killed. I know a dying program when I see one, I do this for a living.

If you continued to read the wikipedia article, you would see that they are working to add 406Mhz response time to the GPS satellite constellation and they are working to add 2-way communication back to devices (obviously future devices) using the MEOSAR system:

[quote=part of the wikipedia article you didn't read]
Supporters of the Cospas-Sarsat system are working to add a new capability called MEOSAR (Medium Earth Orbit Search and Rescue satellites.) In its current (project) form, it is being called the Distress Alerting Satellite System (DASS) by NASA.[7] This system will put SAR processors aboard the GPS satellite constellation and the Galileo positioning system constellation. MEOSAR satellites will be able to provide near-instantaneous detection, identification, receipt of encoded position, and determination of Doppler triangulated position of 406 MHz beacons (exclusively.) MEOSAR assets will report signals from Cospas-Sarsat search and rescue beacons in the 406.0

[The European Death Knot]

You seem well informed.
Explain why the failed birds have not been replaced?
Any idea when and if they will be replaced?

There will be no 406mhz added to GPS. GPS OCX was awarded this week to Raytheon and 406mhz is not part of the package. There is no way to retrofit the existing GPSII system to add 406mhz.

First, the SARSAT program will outlast any and all private satellite programs. The government requires SARSAT capability, and it is used much more than just for public search and rescues. This program will simply not be going anywhere.

Second, the SARSAT program is exponentially better staffed and organized than any and all private satellite programs. The military is involved with all SARSAT rescues (that is a good thing, by the way) via the US Mission Control Center, and the rescue is professionally coordinated; on the contrary, an hourly guy is probably managing SPOT rescues (this is not a stretch).

Third, PLBs perform exponentially better than SPOT. I think this surely has been discussed previously.

Fourth, SARSAT coverage is great. The "failed birds" you mention were simply decommissioned and replaced. GOES-11 covers the western US, GOES-12 covers the eastern US, GOES-13 is on standby in case either 11 or 12 fail, GOES-14 is a spare, and GOES-15, which just launched about 10 days ago, is another spare. The "G" in GOES means "geostationary", so these satellites are fixed in orbit relative to the earth. So, I don't understand your questions on "failed birds" not being replaced. Likewise, the last POES launch (for lower earth orbit, or LEO, tracking) was last year. A new program is to replace the current POES program. What this program will be is yet to be determined (as the White House just dissolved the NPOESS program, which was to replace POES), but there undoubtedly will be something replacing it, as this is a mandatory program necessary for the national interest.

www.sarsat.noaa.gov has a lot of info you may find useful...and sometimes it is nice to visit sites outside of wikipedia.

Your seemingly distrustful and skeptical opinion on our government's (great) program makes me think you're from Utah...