Satnav this morning...

mbunting · Post by **mbunting** » 15 Dec 2006, 08:23

Just a quick bit of info for you.

If your satnav was / is a bit screwey this morning, we're in the middle of a large solar flare geomagnetic storm from the sun, another one is potentially heading this way, which would be interfering with transmissions from/between the satellites and your GPS.

Mine this morning was two or three streets out, even with a 9 sat lock. Turn a corner, and it was bang on, turn another corner, suddenly three streets out again.

Pretty sure this would not be the USA turning on SA again.

f00lzz · Post by **f00lzz** » 16 Dec 2006, 18:14

I was using my Navman 530 between 6:00 and 7.00 and then again after 10:00 till 13:00 and didn't notice anything!!!! I wish I had known about the Solar thingy I would have paid better attention...

alan s · Post by **alan s** » 16 Dec 2006, 23:30

2 Questions:

mbunting:- If you knew you were 3 streets out, why did you need a Sat nav?

foolzz:- Are you sure it wasn't playing up? Did you find your way home OK? Suggest you take a careful look at the surroundings in case you're in a neighbours house 3 streets away.

With a posting like this, you can tell when my Christmas parties start can't you.

Alan S

Post by **CitroJim** » 16 Dec 2006, 23:52

Ahh, solar flares

The memories. They used to cause me much fun back in my days as an HF Radio Engineer. They used to wreck havoc with radio commumications. They were known as SIDs or Sudden Ionospheric Disturbances.

Radio Amateurs love 'em because of the unusual propagation they can give to radio signals. To us pros though they were a pain as they often caused complete radio blackouts for hours at a time. Explaining why to those who wanted a message delivered was not always easy as they would not believe that for once the old excuse of "atmospherics" really was to blame...

They also give rise to Auroras (Northern Lights) to those lucky to live in northern lattitudes. I've never seen one but would dearly love to one day.

Interesting that they give satnav problems though, probabaly as a result of doppler shifts upsetting the timing and hence three streets out

mbunting · Post by **mbunting** » 18 Dec 2006, 11:30

alans

There is a legitimate reason for my toy...

I have a 406 2.1DT and the speedo binacle has some earthing problems, it tells me I'm doing 70 when stopped, and 20 when doing anything else !

It's not the transducer thingy, defo earth on the pcb, which I need to get around to soldering up.

Oh, and the satnav tells me my speed, and also "safety" camera locations.

Plus, it's a toy

alan s · Post by **alan s** » 18 Dec 2006, 21:53

That was more of a "leg pull" than anything, but I agree with that. My son was driving a car that he'd brought up to just under V8 supercar development series standard and was driving it to Canberra a couple of years back where it was (unexpectedly) writted up in a national car performance magazine, with the speedo not operating and asked the other guy in the car, the owner, what speed the Sat/nav was recording. He gave him a figure at which point he backed off...................just as the red and blue "disco lights" lit up behind him, and know what? He had exactly the same reading as the copper!!

So you need to keep a bit of an eye on them. Unfortunately, his mate had it on the passengers side of the car and he couldn't easily see it and with 400+ HP under the foot, it was easy to overstep the mark.
Just out of curiosity, how are prices going for them over there? We are seeing a couple now getting down around the A$500 - A$600 mark, (200 - 250 UK pounds) so getting into the realms of where everybody can afford one.

Alan S

AndersDK · Post by **AndersDK** » 18 Dec 2006, 22:51

Still a bit expensive here in DK. Some £300 and up for named units.
Guess prices will come down soon as many retailers are trying to take their share ...
January sales coming up, we'll see ...

jeremy · Post by **jeremy** » 18 Dec 2006, 23:23

Looks as though they are £100 upwards. I've no idea what does what but there's a good number on this link.

http://www.comet.co.uk/cometbrowse/home ... zone_id=13

micitroen · Post by **micitroen** » 21 Dec 2006, 11:56

Asda (Wal Mart) here have one for sale at £99.....don't know how good it is or whether its upgradable or not.
I have a £200 'Medion' jobby from Aldi stores and it is very good, with the speedo being spot on rather than the cars one which I find overreads by about 5mph at all speeds.
A lot of the other (more expensive ones) have 'bluetooth' and other gimmicks with warnings of speed cameras built in (however this only warns of a 'known' location of a camera).
So it seems that they are now within everyone's reach.

uhn113x · Post by **uhn113x** » 28 Dec 2006, 16:44

Phew!

Lucky you found your way home, mbunting!

I have one of those Road Atlas things - you may remember them. Very good for driving around this little island of ours.

A Satnaff story; an erstwhile colleague needed to get from Coniston Cold (Yorkshire Dales) to Sowerby Bridge (near Halifax). Approximately 30-40 miles in a SW direction.
He entered, er, something, and set off, completely oblivious to the fact that (A) he was heading North and (B) places like Harrogate and Scotch Corner should not have been part of the plan.
He realised the error of his ways when he did spot something he knew.
The Angel of the North .....
Long way back.

bxbodger · Post by **bxbodger** » 28 Dec 2006, 22:31

Don't rely on them as a substitute speedo-they don't compensate for your movement up and down hills as far as I know. The speed figure will only be correct on the flat.....

I always thought these things were a bit like aircon, nice to have but not really neccesary, but I bought Mrs BXB one for xmas as she can get lost in a paper bag, and we gave it a try on boxing day. Much better and more accurate than I thought it would be and I can see why people would use one in preference to an atlas-excellent if you're in the dark in a strange town with no local A-Z: just tell it the road name or postcode and off you go......

We did manage to catch it out once though, taking a wrong turning in order to see what it would do and declining its offer of a 'safe U turn' it quickly recalculated a new route, but about a quarter mile from home it wanted to send us down a green lane long since gated off to motor traffic to keep the 4x4 brigade out-it then realised the error of its ways and recalculated again.

It was interesting after dark-I'd actually bothered to read the manual and set it up to automatically go to dim night setting after dark, but loads of people seem to drive around with them on day setting-extremely bright and distracting to have stuck in the window!!

UFO · Post by **UFO** » 29 Dec 2006, 07:18

I use my satnav nearly every time I go on an out of town trip, even if I know where I am going. I use it for the speed reading.

On a recent 850km round trip for Xmas, I had it set on a speed that I knew the cops would ignore and the speedo on my XM was reading about 7km/h more. We went past several police on the journey and they didn't even flinch. I find that the registration of speed in hills is not such a great issue.

BTW, in Aus over long holiday periods, like Xmas/NY, we have "double demerits" whereby a speeding offence (and others) earns you double demerit points. Therefore if you do something that would normally cost you $$ and say three points, it costs you the same $$ and six points. Having two unseatbelted people in the car can accrue you the maximum allowable 12 demerit points. Taxis and walking then become your most common mode of transport.

What does happen with double demerits is that most people drive like Nannas and usually slice at least 10 km/h off their speed and then drive with half an eye on the road and the other 1 1/2 eyes on the speedo. Good tactic eh

James.UK · Post by **James.UK** » 29 Dec 2006, 15:29

So how do these fings work?? What powers them? Could I swop them between my two cars? How much is involved in fitting them? Do they give compass readings?

Do they speak a language I would understand? i.e. I have trouble understanding Scotsman, Geordies, people from Birmingham, and kids under the age of 16 ish who talk with wobbly hand signals and noddy heads..

.. heh heh ..

Are they open to debate when my g/friend chooses to argue with it? And would they bounce if thrown from a moving car by aforementioned g/f? 8)

More input please..

.

FrenchLeave · Post by **FrenchLeave** » 29 Dec 2006, 17:22

Hi James,

How do they work? There are umpteen satellites (don't know how many - believe about 36) scattered around the globe, put up by the Yanks to control their navigation and weapons systems. They are in geostationary orbit, in other words they hold a fixed position relative to the earth's surface and each one sends out a unique coded signal which contains info concerning its position and the time of transmission. Our receivers lock onto the satellites that are above the horizon and, by decoding the signals, can establish where they are. Older satnavs designed for marine and aero use often just give latitude and longitude and the info has to be transcribed onto charts, but our vehicle ones have a software program that interfaces with a map.

Power is usually obtained from the cigar lighter via a lead. Some have built in aerials and these are easily transposed from car to car. Some give compass readings as well, some give current altitude, some give true speed, some give eta, the choice is yours.

My fairly old (3 years) model has a clear female voice, she sounds remarkably like Fran Godfrey (Terry Wogan show, Radio 2). My wife doesn't like her, she hates the idea of another woman telling me what to do.

No and no.

My map is now getting out of date, usually new roundabouts, the occasional new road. But I wouldn't be without it.

Hope that clears it up.

Derek
_-

bxbodger · Post by **bxbodger** » 29 Dec 2006, 18:17

Do they speak a language I would understand?

You can set them to speak more or less whatever language you want....and you can also download new voices for the newer ones, so should you want Matt Lucas telling you to turn left in 300 yards then you can have him do that!

The hand-held outdoor sport type units (I have a bright yellow battery eater of an Etrex) have been around for years and give you straight navigational data, i.e. grid coordinates, latitude'n'longitude, compass bearings, etc, to be used with an O/S map: this isn't what you want in a car, however..

Car satnav works in exactly the same way but presents the data in an easily used format; a map of the road in 3D showing your progress and orientated to appear the same as the view from the windscreen- absolutely NO knowledge of old style map'n'compass orienteering is neccesary to use a car satnav!

Go and have a look at the demo ones in Comet or Halfwits or wherever- and the 'safety' camera warning chime can be pretty useful too....