greenjersey

Having had an MI and being a pessimist I fear I may sometime have to phone for an ambulance when out cycling. Trouble is I seldom know where I am! (I cycle in Sussex and am always ducking and diving down lanes). Will a GPS give the post code (is that zippcode in the US?) of my location? If not what will it tell me. thanks for any advice.

mrbubl

In the US your cell phone will give your GPS coord within about 10 feet, even if the cell phone is turned off. Check with your cell phone provider as YMMV in the UK.

Zero_Enigma

The GPS will give you your satalite grid in logitude and latitude. (ie. Long N xx.xxxx X Lat W xx.xxxx the N/W can change pending your area in the world. I just know in Canada where I am it's North and West. The 'x' are numbers which define your area as close as 3-10 meters to your position)

I do believe you can search up postal codesif you have the city maps loaded into the GPS. I vauagely recall that you can do that with the Canada MetroGuide which I do believe is universal with all other countries versions. Basically if memory is correct (someone jump in and correct me if I'm wrong) that you can enter your address you want to go to in the GPS and the GPS will (if the city maps are loaded in) be able to look up the address much like a paper map.

If you are at https://maps.google.ca or www.mapquest.com if you move the mouse around the map you will see numbers moving around. Those numbers are the GPS position for where your mouse is on that location on the map. If you pick a location at either site and note the numbers there you can copy those numbers down and enter into the GPS for safe keeping and as a route later on.

head_wind

If you would be able to call for help wouldn't it be satisfactory to say
something like "I am on road xxxxx and am about y miles north (or other)
from where xxxxx intersects road zzzzz." If that is satisfactory then a
mapping GPS _with_ the local map installed should suffice. You would
need sufficient presence of mind to read the map.

I live in a town of ~.5 million population which has (I think) about 20
zip codes. Does postal code have that much finer resolution to be
sufficient for ambulance routing??

maximushq2

Yeah a portable gps with local maps and streets is nice. I have a Magellan Meridian Color gps and loaded up direct route which shows each street and you can use to get turn by turn directions if you wanted. I used to use it in my car for trips before I got a vehicle only type gps with touch screen that makes it easier to navigate while driving.

greenjersey

UK postal codes are, I believe used by the emergency services. They will tie the location down to a very small area. In urban areas to just one building but I'm not sure how it works in the countryside.

dbg

Well you most likely could find the lat/long coordinates on your GPS and give that info verbally to an emergency service who could most likely use it to find you. But you might want to review how to find that info quickly so that you're ready when you need it.

And again, in the US virtually all cell phones and services have 911 emegency service with built in GPS location.

Olden Crow

My little Garmin GPS connects to the handlebars and the map will zoom in and out, it shows all the street names. If I had no idea where I was in a strange city, I could punch a few buttons read the GPS map to find out and then tell ambulance dispatch, "I'm on Apple Street, betweem Berry Ave. and Cherry Lane".

The maps are stored on computer CD's or DVD's, and upload the ones you need into the little GPS unit.

Dahon.Steve

A GPS will not give you a postal code. An ambulance will have to locate you by the name of the cross street you are located in. If the situation is grave, you may have to knock on someone's door or stop a person on the street and ask them where you are.

randomgear

Lat year, a driver drove off a very high off ramp coming over the Zakim Bridge from Boston. He landed in a gravel pit, and was able to call 911, but had no idea where he was. The state police were able to track his location from his cell phone. I think he survived, his passenger was not so lucky. I don't remember how long it took to find him.
Obviously, knowing what street you are on and the street number of the nearest building is the most efficient way.

bikingbrit

A GPS will always tell you the latitude and longitude of your current location and this is much better than a mere postal code. Most police now have GPS so they would be able to find you.

Some but not all cell phones have GPS.

Even without GPS, a cell phone call can sometimes be traced to the tower that it went through and this can help police find you. Check with your phone company or police to be sure they have this capability.

BTW I used to live in Lewes, about 7 miles east of you. I always wanted to ride my bike down the A27 to Kingston but I was only 10 years old and my parents wouldn't allow it...