Ham Radio operator tracking?

Question by 1992dodge: Ham Radio operator tracking?
So about four years ago I was in a ham radio club that showed off this cool technology. I just now decide that I would like to know what it is.

They had a computer on and you could see a map of the USA. When you zoomed in on a specific location you could see ham radio call signs either siting in one location or moving along roads. Now they explained that it had something to do with digital radios but not sure if they said anything to do with GPS. So you could follow a operator when his radio is on or in use. I would also like to know the uses of this technology.

So if anybody knows what I'm talking about please let me know. Thanks

Best answer:

Answer by Chris
it's called APRS, or Automatic Packet Reporting System. Mobile ham radio stations transmit a short data packet with their GPS position every so often, which is picked up by fixed stations and relayed around the Internet.

There are a few web frontends to APRS, try:
aprs.fi (this is probably what you saw)
openaprs.org
googleaprs.com
http://info.aprs.net/index.php/Main_Page#External_links (aprs wiki, has a great many sites)

APRS is also used for things other than GPS, for example many remote weather stations have APRS uplinks and periodically report temp/humidity/wind/etc over APRS. This is useful because anybody can then access the data.

hope that helps!

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