APRS / Amateur Radio and snowcats

[kgracey]

Hey there,

Wondering if any of you have set up APRS (http://en.wikipedia.org/wiki/Automatic_Position_Reporting_System) in order to transmit your location to the internet. WIth APRS you can connect an HT 2-meter radio with GPS unit and send your location back to your home where it is displayed on Google Maps or Google Earth.

Anybody experience with APRS? I'm going to set up a system and see how well it works. Has a few dependencies, of course, like ability to transmit via repeaters if that's what's necessary (usually is in the mountains) and a home base with functional broadband. But this stuff gets more useful every day.

KI6HBT

 

[MNoutdoors RIP]

Hey there,

Wondering if any of you have set up APRS (http://en.wikipedia.org/wiki/Automatic_Position_Reporting_System) in order to transmit your location to the internet. WIth APRS you can connect an HT 2-meter radio with GPS unit and send your location back to your home where it is displayed on Google Maps or Google Earth.

Anybody experience with APRS? I'm going to set up a system and see how well it works. Has a few dependencies, of course, like ability to transmit via repeaters if that's what's necessary (usually is in the mountains) and a home base with functional broadband. But this stuff gets more useful every day.

KI6HBT

Ken there are quite a bunch of tracking devices now out. some being just logggers and others realtime, Trackstick, and others

Here is one using real time using aprs I think don't ask how I know.......


http://www.brickhousesecurity.com/small-covert-gps-tracker.html


It is a good way to find where Mainer is looking at Cats at.
and then soon as he leaves the area you swoop in for the Buy.

 

[Bobcat]

I have a Kenwood D700A and a D7A that have APRS built-in. I haven't used them in a while, but will be installing the D700 in my work truck soon.

When I used it regularly, it worked just fine. I even bounced a packet off the space station once (they have a D700 up there!). Besides earth-based repeaters and the space station, there are quite a few Ham LEOs up there that will repeat your APRS packet. You can also send Internet email via APRS, just can't receive it.

With or without a radio, you can see all of the APRS traffic near you or around the world with WinAPRS. It's free and can be had here... http://www.winaprs.org/

 

[kgracey]

Bob,

Funny, that's the radio I was looking at since it has the built-in TNC:

http://www.kenwoodusa.com/Communications/Amateur_Radio/Portables/TH-D7A(G)

Could you go over the connections for me, just so I got the concept? I assume it's something like this:

GPS=>D7A Radio => ))) 2m (((( Radio=>TNC=>PC running APRS software

What I'd really like to do is allow my wife to see my whereabouts on the snowmobile.

Thanks!

 

[Bobcat]

Sometime tomorrow I'll fire it up and get some pictures and video for you of the complete setup. You have it right, though there are other options.

If you don't care about having a visual (map) indication of your whereabouts, another D7 in the house would show your long/lat, bearing, and distance from the house.

If there is a digipeater/IGate within range, you wouldn't need another radio in the house, just an Internet connection for yourcomputer.

 

[Bobcat]

Oops, forgot to do the picture thing. Will get on it tomorrow.

 

[Bobcat]

Well, here is a quick and dirty diagram.

There are 4 possible routes from the mobile radio to the home computer:

1. Radio>Home Radio>Home Computer
2. Radio>*AO-Sat Digipeater>Home Radio>Home Computer
3. Radio>Digipeater>Home Radio>Home Computer
4. Radio>I-Gate>Internet>Home Computer
*the AO-Sat could also be the ISS or Space Shuttle



Obviously if your radio on either end did not have a TNC, you would have to add one between the mobile GPS and radio, as well as the home radio and computer. By the by, APRS is not limited to 2M.

 

[Bobcat]

Another option on the 'home' side is to use an 'APRS ready' GPS instead of a computer. AvMap makes two models, the G4T and the G5. I have the G4T as my mobile unit. It does it's normal GPS stuff (mapping, routing, etc) as well as displaying the location of any APRS stations picked up by the radio. The darn thing even has an A/V input for backup cameras, etc.