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guitar_plr
02-13-2005, 12:46 PM
Does anyone have any experience or any information on communicating with satellites using ameteur packet radio using a BASIC stamp?· I am interested in using the satellites for long-range communication of gps location data for use in a tracking system.·

I know I would need an Ameteur Radio license.· I've already seen this post but I was wondering if there was more info out there:·http://forums.parallax.com/showthread.php?p=516584·The method of using a·GSM module·to transmit data seems a little more straight forward than packet radio, but I really couldn't find any online resources pointing to a place to buy it.

Please share any knowlege on either method of communicating or some project details.

Thanks!

steve_b
02-13-2005, 01:10 PM
Hi guitar_plr,

in that referenced thread, I had mentioned APRS.·
Here's a intro site for APRS: http://www.arrl.org/tis/info/HTML/aprs/
There are a tonne of Amateurs out there playing with it for sure.·· But as far as Satellite stuff....not sure.
I know there was an Amateur sat launched a few years back (I remember the news about the build....I'm sure it's up there by now).· I don't know it's function or what it offers. But here's·a link: http://www.arrl.org/tis/info/satellite.html

Certainly you'll need·a radio, and if it has a data port then you're laughing, otherwise you might have to 'manipulate' your signal for transmission.
Baycom used to be a make for packet modems....don't know if they're still around though.

here's another: http://www.dxzone.com/catalog/Operating_Modes/Satellites/


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Steve
http://members.rogers.com/steve.brady (http://members.rogers.com/steve.brady)
"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

upand_at_them
02-13-2005, 10:35 PM
The APRS repeater network operates at 144.390 MHz.· You can setup a small system with a radio and a TinyTrak.· I would test out the location to see if you can hit a repeater from there before exploring other options.· Unless you're in some far off place you shouldn't have trouble getting your signal repeated to an I-gate.

Just please keep in mind that this network exists for all Hams.· So don't so something inconsiderate like transmit every couple of seconds.

Mike

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steve_b
02-13-2005, 10:52 PM
I've heard of people abusing the repeaters thinking they can't be found as they're anonymous.
Well, the repeater site would turn off for extended periods in hopes of the abuser moving on, but they'd always come back.

It was when some Ham'ers had a game a 'foxhunt' that they tracked him down.
They didn't burn him out of his castle or anything, but the federal agency was notified (can't remember what country it was in) and the guy got the point.

He had been transmitting data over the repeater every minute and people were having problems getting on the repeater.· It's not like the Internet, where they can block an IP or MAC address....but there are a lot of repeaters that you have to 'log-in' to (You need to know the access code).

So you might want to sit in on a local HAM meeting to get some idea of etiquette.
In Canada, if you have your BASIC qualifications you are limited to 30Mhz and above (2m and smaller) and with a 250W output.
The more exciting stuff is in HF, so we need to get our ADVANCE qualification AND morse.· But, morse up here has been reduced to 5words per minute to open up the whole band (used to be 5 and 12).· I don't think the US has an morse endorcement anymore....but you may need your TECH qual. to get it.

Anyhow, it's a great hobby as the infrastructure is already there.
We have a lot of HAM gear on some of our towers.

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Steve
http://members.rogers.com/steve.brady (http://members.rogers.com/steve.brady)
"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

upand_at_them
02-14-2005, 03:53 AM
I don't know about other countries, but in the U.S., APRS packets must contain the FROM and TO callsigns.· Someone could certainly use a fake callsign or use someone else's, but that would get you into a lot of trouble with the FCC.

Mike

JKtech
02-16-2005, 11:23 PM
Ham Satellites are not in geosinc. ordit so they are only above a givien area for a short time. To Communicate you would have to track the satellite to see when and where it is. I am not saying it is imposible but more complicated. Like what was said earlier lot of hams have what is called Digipeaters for packet and APRS. The best bet is to contact local hams in your area.

By the way APRS uses the UI frams so you do not need a TO callsign but you do need a FROM callsign. With that in mind there is no guarentee of reception.