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Hill climbs or on the flat are both taken care off by the satellite calculations as your location is taken care of as a point in space, the Amundsen II sat nav even always displays the altitude on screen. the only thing that could confuse the calculated speed is going round a bend but that would be minimal.
 

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In the Soul, I get 4 miles per kilowatt in this colder weather. It costs 5p per kilowatt on Octopus i.e. 1.25p per mile.

Our Yeti returns 47mpg overall (on the computer) with most mileage on rural roads and often pulling a trailer.
 

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I believe satnavs/gps are only accurate on the flat, which the majority of roads are, unlike hill climbs. My sister in law has also told me that colleagues who are keen walkers say that apps which determine steps and distance read about twice the true value.
I had wondered about that and it’s something I must investigate further. GPS will calculate altitude providing you are in the footprint of a least four satellites, so surely it wouldn’t be that difficult for the receiver to calculate a distance vector based on ground track and height climbed? I don’t know but will try to find out.

Step counters don’t generally use GPS, relying on inputs from accelerometers, gyroscope and compasses in the more sophisticated ones. They are notoriously unreliable. The step counting works but how long is a step? It varies from person to person, the speed you are walking and the terrain.

It still leaves the question of why three identical GPS receivers, doing the same journey, come up with different answers. Nothing much on the box tonight, must see if I can find some answers. 🤓

Just noticed Urrell’s post!
 

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I might have some answers to my own questions.

Although the atomic clock on a satellite is accurate to 2 nanoseconds a year, the quartz clock in the average receiver is only accurate to 10 nanoseconds a day. That will explain the differences between individual identical receivers.

Unlike what is believed by many (including me, before now) , speed is not calculated by time taken from position to position, where inaccuracies can show. The calculation is done on a doppler shift of the frequency of the timing signals. This would be unaffected by hills and so the speed divided by the time will give the distance.......phew!
 

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The project dept at work used gps for recording and identifying the location of new mains laid, it was rubbish and was sometimes over 100mts out. I hope they have improved on those that they had.
 

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All of you apart from Graham are driving oilers. (apples & pears)
Mine is PETROL !
I'd like to hear any other petrol owners that can achieve over 50mpg
Yeah, and I'm partly cheating since I've got help from an electric motor! 😇 😇 😁
 

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I believe satnavs/gps are only accurate on the flat, which the majority of roads are, unlike hill climbs. My sister in law has also told me that colleagues who are keen walkers say that apps which determine steps and distance read about twice the true value.
Not around here, dear!!

And beware anyone using sat navs, GPS and atomic clocks around Mid Wales area . MoD have reported they will be "playing" with some electrical gubbins from Sennybridge that will affect them.
 

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Not around here, dear!!

And beware anyone using sat navs, GPS and atomic clocks around Mid Wales area . MoD have reported they will be "playing" with some electrical gubbins from Sennybridge that will affect them.
I think that exercise finished in September. They are playing in Scotland at the moment.

We have drifted way off topic again! Not you Graham - my fault.
 

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I think that exercise finished in September. They are playing in Scotland at the moment.
Not according to the local news, seems to now be running until the middle of this month.
 

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Not according to the local news, seems to now be running until the middle of this month.
You are quite correct Sir! I was reading an outdated list.

The current dates for GPS jamming on Sennybridge are: 9-20 November, 7-18 December and 11 - 22 January 2021.

I was out and about in the Cambrian Mountains yesterday and my satnav seemed to be working OK.
 

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Why are they jamming GPS? Sneaky beaky stuff maybe?
Military exercises is the normal reason.
As this seems to be centred on the Epynt Ranges I suspect it is to teach the cannon fodder how to read maps and destroy things without electronic help.
 

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Or the best way of defending against an attack from cruise missiles and drone aircraft, is to block the GPS signals they rely on to know where they are and where their targets are.
 
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Military exercises is the normal reason.
As this seems to be centred on the Epynt Ranges I suspect it is to teach the cannon fodder how to read maps and destroy things without electronic help.
These exercises are being based all over the place, not just on army ranges. Flintstone is much closer to the answer. It could also be the way to hinder the smaller drones which some idiots like flying near major airports.
 

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Mobile 'phone coverage is lost near RAF Fylingdales. I'll check the satnav sometime.
 
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Mobile 'phone coverage is lost near RAF Fylingdales. I'll check the satnav sometime.
There are very few mobile transmitter masts in that hilly area and that is the most likely reason. Unlikely that your satnav won’t be working though.
 
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