Kerry.

Rebate??? huumm bit of a miss worded option really as some might not think they use it (or need it, or want it) but wanting a rebate on GPS altitude, well that's really a bit of a wasted cause. Cheers, Kerry. I never get lost everybody keeps telling me where to go

Rebate??? huumm bit of a miss worded option really as some might not think they use it (or need it, or want it) but wanting a rebate on GPS altitude, well that's really a bit of a wasted cause. Cheers, Kerry. I never get lost everybody keeps telling me where to go

Anders, some figures. Based on current constellation (today) at N50 you should have a 12 satellites in view (down to horizon) 11.7% over a 24 hour period. At N60 you'll see 12 for 12.4% over a 24 hour period. Now if one had a receiver with more than 12 channels at N60 there would be a max of 15 sats in view for 4.1% of the time but at N50 the maximum numbers one could see is 14 (5.5% of the time) Cheers, Kerry. I never get lost everybody keeps telling me where to go

Anders, some figures. Based on current constellation (today) at N50 you should have a 12 satellites in view (down to horizon) 11.7% over a 24 hour period. At N60 you'll see 12 for 12.4% over a 24 hour period. Now if one had a receiver with more than 12 channels at N60 there would be a max of 15 sats in view for 4.1% of the time but at N50 the maximum numbers one could see is 14 (5.5% of the time) Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by Anders: There is another thing. It seems to me that where I live (N 57), I can more frequently get many sats at the same time, compared to if I travel south to, say, N 50. Does anyone know if that's because the satellites turn around and starts going back south again about where I live, so that I can receive them more often than if I was closer to the equator? That seems logical to me, but I'm not sure if I'm correct in my assumption. Basically there are no satellites over either of the poles or even close to the poles. As one goes further north (or south) one also sees satellites over the poles (other side of the world). Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by Anders: There is another thing. It seems to me that where I live (N 57), I can more frequently get many sats at the same time, compared to if I travel south to, say, N 50. Does anyone know if that's because the satellites turn around and starts going back south again about where I live, so that I can receive them more often than if I was closer to the equator? That seems logical to me, but I'm not sure if I'm correct in my assumption. Basically there are no satellites over either of the poles or even close to the poles. As one goes further north (or south) one also sees satellites over the poles (other side of the world). Cheers, Kerry. I never get lost everybody keeps telling me where to go

WAAS is really a system caught up in the before and after syndrome. The cost for many countries is really totally prohibitive when comparing the 12 odd billion $'s for the basic GPS system todate, which gives world coverage and the 5 billion and counting for WAAS which still isn't even fully implemented and only provides limited coverage anyway. Will be interesting to see what happens in time. Cheers, Kerry. I never get lost everybody keeps telling me where to go

WAAS is really a system caught up in the before and after syndrome. The cost for many countries is really totally prohibitive when comparing the 12 odd billion $'s for the basic GPS system todate, which gives world coverage and the 5 billion and counting for WAAS which still isn't even fully implemented and only provides limited coverage anyway. Will be interesting to see what happens in time. Cheers, Kerry. I never get lost everybody keeps telling me where to go

Important for a waypoint, no. Cheers, Kerry. I never get lost everybody keeps telling me where to go

Important for a waypoint, no. Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by Gunther:Just curious but why does the DoD have these figures as imposed limits - to stop space travel navigation using commercial GPS? Well if your capable of exceeding those limits you've certainly got different intentions than what any civilian user would be into. Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by Gunther:Just curious but why does the DoD have these figures as imposed limits - to stop space travel navigation using commercial GPS? Well if your capable of exceeding those limits you've certainly got different intentions than what any civilian user would be into. Cheers, Kerry. I never get lost everybody keeps telling me where to go

Besides what might be "normal" the official accuracy before one starts hiding under trees, behind buildings, in canyons or entertaining geo storms is less than 13m (43 feet) 95% of the time world wide average. Expected worst case scenario is less than 36m (118 feet) 95%. Cheers, Kerry. I never get lost everybody keeps telling me where to go

Besides what might be "normal" the official accuracy before one starts hiding under trees, behind buildings, in canyons or entertaining geo storms is less than 13m (43 feet) 95% of the time world wide average. Expected worst case scenario is less than 36m (118 feet) 95%. Cheers, Kerry. I never get lost everybody keeps telling me where to go

As far as I'm aware DoD have regulations which control the upper limits of consumer grade GPS receivers for speed and operating height. Those figures I thought were 60,000 feet and 999mph max. Now what receivers actually (really) exceed some fairly important max limits for consumer grade units. Cheers, Kerry. I never get lost everybody keeps telling me where to go

As far as I'm aware DoD have regulations which control the upper limits of consumer grade GPS receivers for speed and operating height. Those figures I thought were 60,000 feet and 999mph max. Now what receivers actually (really) exceed some fairly important max limits for consumer grade units. Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by Criminal:My question is: Will this system be compatible with the receivers we already have? No, not without at least some software changes and, harware I wouldn't be to sure about at this stage. From discussion and plans to date both systems will certainly have the capability to be compatible at a system level. However by the time Galileo is operational the currect GPS receivers today will be basically obsolete (as such) anyway with the current GPS moderization plans specially the dual frequency civil service. The current receivers won't be compatible with a dual frequency GPS system but from all accounts the existing recievers will be backward compatible. Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by Criminal:My question is: Will this system be compatible with the receivers we already have? No, not without at least some software changes and, harware I wouldn't be to sure about at this stage. From discussion and plans to date both systems will certainly have the capability to be compatible at a system level. However by the time Galileo is operational the currect GPS receivers today will be basically obsolete (as such) anyway with the current GPS moderization plans specially the dual frequency civil service. The current receivers won't be compatible with a dual frequency GPS system but from all accounts the existing recievers will be backward compatible. Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by jfitzpat: quote:Originally posted by Bagbug: http://www.gpsinformation.net/mgoldreview/sportrak-pro-rev.html Amazing reception under tree cover ! Bag I think you might reading too much into the review. -jjf Me thinks so too once one sees comments like detecting differences of 0.8m between datum's with a single freq unit with auto-averaging it sort of makes one a little cautious. Cheers, Kerry. I never get lost everybody keeps telling me where to go

quote:Originally posted by jfitzpat: quote:Originally posted by Bagbug: http://www.gpsinformation.net/mgoldreview/sportrak-pro-rev.html Amazing reception under tree cover ! Bag I think you might reading too much into the review. -jjf Me thinks so too once one sees comments like detecting differences of 0.8m between datum's with a single freq unit with auto-averaging it sort of makes one a little cautious. Cheers, Kerry. I never get lost everybody keeps telling me where to go

With certain handhelds there are ways to post process against data from something like a CORS but off course the hardware/software in a handheld isn't as refined as some of the more "clever" receivers. From these handhelds the data does need to be recorded in rinex to a computer using some specific software. Sub-metre is still a big ask especially when one considers the satellite URE is probably generally more than a metre but some of the Block IIR's are now less than a metre but of course there's only about 6 of them. But one could process against precise emphemeris but that's not available until at least 2 weeks after the event and when it's all said and done one is probably spending 98% of the time to improve the accuracy by 2% It may be surprising but even with the 530's in standalone pure navigation mode the SPS accuracy isn't going to be all that much better than some handhelds. In other modes now that's a different story. Cheers, Kerry. I never get lost everybody keeps telling me where to go

With certain handhelds there are ways to post process against data from something like a CORS but off course the hardware/software in a handheld isn't as refined as some of the more "clever" receivers. From these handhelds the data does need to be recorded in rinex to a computer using some specific software. Sub-metre is still a big ask especially when one considers the satellite URE is probably generally more than a metre but some of the Block IIR's are now less than a metre but of course there's only about 6 of them. But one could process against precise emphemeris but that's not available until at least 2 weeks after the event and when it's all said and done one is probably spending 98% of the time to improve the accuracy by 2% It may be surprising but even with the 530's in standalone pure navigation mode the SPS accuracy isn't going to be all that much better than some handhelds. In other modes now that's a different story. Cheers, Kerry. I never get lost everybody keeps telling me where to go

If the past life was the 45 era then having had come from several past lifes before that the 45 was ahead of its time and one reason why it probably hung on/in for much longer than anybody might have expected (or some might have wanted ). However the difference in the lock on times was something I never really could see much of an issue with, especially when one considers that to update/download a complete almanac from scratch takes about 12.5 minues. Now for a unit (any unit) after being switched off for some period of time to start navigating in around 30 seconds could be a bit of a worry if it's using "past" information and not "current" information (that takes time to download). Many things could have changed in that switched off period be it several weeks or even 24 hours? Anyway back to some lock on times, which by the way were done pre-sa (I know a past life just gone) Warm Start average (24 hours Off to Lock) GPS45XL : 44 seconds GPS48 : 16 seconds Difference 28 seconds Hot start average (Sats locked, switched Off then On) GPS45XL : 20 seconds, 23 seconds GPS48 : 11 seconds, 14 seconds Bugga all between them really so what a few seconds anyway. The predecessor to the 45XL (45) was on average a little slower at a warm start at around 106 seconds but certainly gave nothing away to the 45XL or 12 channel 48 for a hot start. Just some thoughts from the past. Cheers, Kerry. I never get lost everybody keeps telling me where to go

If the past life was the 45 era then having had come from several past lifes before that the 45 was ahead of its time and one reason why it probably hung on/in for much longer than anybody might have expected (or some might have wanted ). However the difference in the lock on times was something I never really could see much of an issue with, especially when one considers that to update/download a complete almanac from scratch takes about 12.5 minues. Now for a unit (any unit) after being switched off for some period of time to start navigating in around 30 seconds could be a bit of a worry if it's using "past" information and not "current" information (that takes time to download). Many things could have changed in that switched off period be it several weeks or even 24 hours? Anyway back to some lock on times, which by the way were done pre-sa (I know a past life just gone) Warm Start average (24 hours Off to Lock) GPS45XL : 44 seconds GPS48 : 16 seconds Difference 28 seconds Hot start average (Sats locked, switched Off then On) GPS45XL : 20 seconds, 23 seconds GPS48 : 11 seconds, 14 seconds Bugga all between them really so what a few seconds anyway. The predecessor to the 45XL (45) was on average a little slower at a warm start at around 106 seconds but certainly gave nothing away to the 45XL or 12 channel 48 for a hot start. Just some thoughts from the past. Cheers, Kerry. I never get lost everybody keeps telling me where to go

All things are relative to cost and basically refinements in the software capability. Still only a single frequency receiver with accuracy dependent on the mode of operation. Cheers, Kerry. I never get lost everybody keeps telling me where to go