Locator squares for IOW

Wight locators

Maidenhead/WAB

Maidenhead Locators for the Isle of Wight

Click on link for large Maidenhead 500KB  Maidenhead Large Clicking on map just gives a slightly larger image.

 WAB Locators for the Isle of Wight

WAB Large Click on link or map for large map 500KB 

 

The use of GPS

For critical navigation do not use GPS unless you are certain of what you are doing! The following are only my observations.  For accuracy in conjunction with a map a GPS must be set to the same coordinate system to which the map was drawn. In the UK all the maps I have seen appear to be based on the Ordnance Survey. Therefore the GPS must be set to the OSGB grid and OSGB datum. This involves two settings on my Garmin Etrek. (For maps with a Lat/Long grid the datum should still be OSGB) I have noticed a discrepancy of around 200 yards (Metres) when my GPS was set to the WGS84 (Default) datum.

The GPS is a useful tool for navigating on land, while walking it keeps locked when in my shirt top pocket, except under heavy tree cover when holding up in my hand improves things. It will sometimes lock indoors when there is not too much above. Except when surrounded by lots of tall buildings it works well in the car under the windscreen. Most modern SatNavs , introduced since I produced this page do not seem to have co-ordinate inputs so will be of little use. They also need to be used with care, some have been known to direct vehicles along unnavigable roads, look at a map! Current SatNavs do have Lat/Long coordinate entry. I suspect this is WGS84.

An unknown destination may be reached with it's help by keying in, or transferring from a computer, the coordinates or route. The coordinates may be found by looking at a map or if you know the postcode going to a site like http://www.streetmap.co.uk/ which will give a map and coordinates. Note that a location obtained like this is not precise. A postcode derived location can be perhaps half a mile out! Most GPS units may be used with a computer running an accessory mapping CD, which should make things very easy.

 

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