View Full Version : Suunto X-9.. has anyone used this
I'm curious as to know how well the GPS compares to GPS stand alone units.
My friend has it and says that the GPS is good, but requires calibration many times (which isn't hard, just a special 360 rotation with the watch). He still doesn't trust it enough to not carry with him a dedicated GPS, though. He does say, however, that finally! the altimeter works because it is no longer based only on pressure.
He also says that the Operating System is massively improved over the old Suuntos.
He recommended that I wait until the second generation comes out around Christmas or early this year (his estimate), because generally they will be far better.
HTH,
Solid
Bill Harsey
08-07-2004, 08:59
I've not used or owned the Suunto X-9 but have owned and worn the Advizor for a couple years now. The altimeter seems to always be within about 100 ft. (one tree length) at elevations from sea level to 9700 ft in my experience to date. Watch also seems to be working normally after wearing it while shooting the .416 Remington magnum this last week. I hate the "reset compass" drill. Don't try the compass while on commercial flights, something really screws it up.
Bill, the X9's compass/altimeter/GPS reset drill, again according to my friend, who owned both the advizor and freelander (he uses these watches a lot), is much simplified over the older models. It's interesting to hear that your advizor's altimeter worked within 100ft, as I hear that the success of this function is almost unique to each individual watch. Safe to say, several of my friends who have owned advizors or freelanders have had massively variable performance from the altimeter, we believe because it is based on barometric readings.
Solid
Bill Harsey
08-07-2004, 12:03
Just like pilots have to set the barometric pressure prior to any flight for a good altimeter reading, I guess getting a good setting on the watch is the key.
geronimo
08-08-2004, 21:23
That is very true. If you don't reset the pressure reading right before you want to use the altimeter it is very hokey. I usually get the current baro pressure reading and set the altimeter on my watch then I'll stay out of air-conditioned areas or places where the pressure will drastically change and it works pretty well. Kind of a pain in the ass but it is nice having a compass with you all of the time.
Footmobile
08-08-2004, 21:36
The newer generation models have a "barometer/alititude lockout" function so that the computer stores average air pressures at known alitudes and lowers the error % due to strange changes in the barometer.
The technology is getting better, but I wouldn't trust any watch based GPS over proven civvy units like a Garmin. In a couple years, maybe, but not yet.
That said aren't the civie GPS's intentionally off x number of degrees/mils vs the military issued GPS or is that just a nasty rumor?
Footmobile
08-08-2004, 22:52
Nasty rumor.
There used to be crypto on Military GPS that got a more accurate reading than civilian models, but was shut off a number of years ago. They stil have the ability to turn the crypto feature back on, but I don't think we could function nearly as well as we do because civilian GPS's are in such high use by so many units.
Thanks for setting me straight.
The intentionally added 'error' to the GPS signal is called Selective Availability. Its not actually a 'crypto' signal; it was a deliberate offset added to the C(A) (uncoded civilian) signal. It was not added to the P(Y) (coded government) signal, thereby allowing someone with a P(Y) enabled receiver to get SA-free data. SA was removed from day-to-day use by order of then-President Clinton. Actually, this was not a bad move, considering the sheer number of civilians using it, from commercial airlines to search-and-rescue units to ships asea.
This does not, however, mean that the need for a COMSEC-keyed PLGR has vanished. The encrypted P(Y) code that only a keyed receiver can pick up provides protection against spoofing, and even a degree of protection against jamming (versus both an unkeyed military receiver and a civilian receiver). Although there has been no observed threat spoofing signals to date, the Iraqis did employ jamming equipment during OIF I, so the threat does exist.
Later this FY, units will begin receiving the Defense Advanced GPS Receiver (DAGR). This PLGR replacement weighs half as much, and is 2/3 the size of the current PLGR. Increased capability comes in the form of reduced time to first fix, the ability to receive two encoded signals at once (which greatly increases accuracy through better ionosopheric interference reduction), easier key/rekey procedures, and the inclusion of the Selective Availability/Anti-Spoofing Module, which greatly increases the anti-spoof/anti-jam capabilities of the receiver, and also increases the security of the coded signals. So, very shortly the advantage of using small, commercial GPS receivers may not outweigh the enhanced performance of a government receiver.
Footmobile
08-09-2004, 09:57
Originally posted by Razor
The intentionally added 'error' to the GPS signal is called Selective Availability. Its not actually a 'crypto' signal; it was a deliberate offset added to the C(A) (uncoded civilian) signal. It was not added to the P(Y) (coded government) signal, thereby allowing someone with a P(Y) enabled receiver to get SA-free data. SA was removed from day-to-day use by order of then-President Clinton. Actually, this was not a bad move, considering the sheer number of civilians using it, from commercial airlines to search-and-rescue units to ships asea.
Yeah, thats what I mean't!:D
Thanks for explaining it in detail.
Just proving that I do earn my keep here at work. :)
Nice explanation. I'm not sure our army uses the same PLGR but its massive.
You mean the playskool toy?
:)
That about covers it yeah.