Anyone using APRS?

[adventureduo]

We would like to setup APRS in our rig in case something happened to us .. our family/friends will know where we are.

Went to the ham radio outlet today to see what they could do for me my setup (Yaesu 2800m and Baja540c)... and it appeared it was going to be about $300 to do what i wanted. I would need to get a complete kit that included a GPS antenna because they couldn't figure out how to setup a cable for my GPS.

Does anyone know of a way to connect a Ham transmitter to a Lowrance unit? I have the big marine plugs on the back.

Anyone use Byonics stuff? Tinkpak?

Any insight on this project would be greatly appreciated. Im just learning about it.. today is day 1 for me.

[DaveInDenver]

Wouldn't a Kantronics MT1200G do what you need? That's probably the $300 option you mentioned, right? Otherwise you could use any TNC, but then you need a laptop and that interfaces the GPS to the TNC. I thought the MT1200G did all the GPS interfacing to the radio.

[adventureduo]

yep thats the unit they wanted me to buy... $276 bucks with it's own antenna. They didnt have one at the store.. 1 left in San Diego store in the USA. I dont know i didn't think it was gonna be that much $$.

[DaveInDenver]

yep thats the unit they wanted me to buy... $276 bucks with it's own antenna. They didnt have one at the store.. 1 left in San Diego store in the USA. I dont know i didn't think it was gonna be that much $$.

If you have the GPS->laptop part handled, then just a regular old TNC would be less, probably about $200 or so. This is the part that packetizes the data from the laptop for transmission on the radio. It basically plugs into mic plug and speaker output for the RX/TX. The Kantronics unit looked cool because it integrated a GPS chipset into the box.

[adventureduo]

Dave, i think i have decided to pass for the following reason..

My buddy just said his dad was just traveling through Texas about a hour ago and dropped off the tracking because he couldnt hit a digi-repeater. There simply weren't any in his general area. This kind of defeats the purpose in my eyes.

I think i will go with the Spot Satellite messenger. I want the unit to work anywhere, anytime. http://www.findmespot.com/

[ntsqd]

As a point of interest, doesn't your 540 output NEMA (?) sentences? I know some do (my 3000MT does), but where you go from there is beyond me.

[adventureduo]

I have no clue, i have a email into Lowrance to check on tracking. I assume marine use must have something.. since they need to be tracked even moreso than us.

[ntsqd]

Some of the Lowrance's have this output so that they can "talk" to marine autopilot systems. Conceivably that data string could then be broadcast to something that understands it.
How the APRS stuff actually works is not in my knowledge base.

[craig]

It sounds like you went in a different direction, but I'll comment anyway since others might care. I've found 3 common ways to setup APRS.

1. Kenwood D700 (or new flavor) with APRS all built in. Just plug your high-end GPS into it and it will both beacon your position out the radio, and display received APRS data on the GPS.

2. A TNC. GPS plugs into TNC, TNC plugs into radio. The micro-usb can be setup to work this way. The GPS sends the position (NMEA0183) to the TNC, which then sends it out via the radio. The radio receives APRS data, sends them to the TNC, which then translates them into NMEA0183 sentences and sends them to the GPS.

Beacon: GPS->TNC->Radio->airwaves
Receive: Airwaves(APRS)->Radio->TNC->GPS

Again, the GPS must be a high end unit as it needs to support NMEA0183 Input as well as NMEA0183 output. The Garmin 60 and 76 series do this for example. I"m not sure about the unit you have.

3. The original way to do APRS was with a laptop added to the mix. This gets harder to setup, but there are some pretty cool things you can do with a laptop in there. For example, you can plot positions of other APRS beacons in OziExplorer with the OziAPRS software package (I'll be adding this to Overland Navigator next year too).

If everyone in your Expedition Team / Convoy has at least an APRS Beacon on board you can keep track of all of them (no repeater required). This is valuable both as a leader and as a follower. The leader can keep track of stragglers, or if you are following and the leader is beaconing then you can see where he is.

The basic setup here is:

- GPS plugged into the laptop (Any GPS that has a real or virtual COM port and that talks NMEA0183 Output. NMEA0183 Input is not required since you will not be using the GPS to display others locations. You'll use the laptop for that.

- APRS Software such as OziAPRS, xastir, UIView, or one of the many other APRS programs out there.

- Most people also use AGWPE or Packet Engine Pro as a sort of "driver layer" between the software and the TNC. One thing cool about this software is that you can setup AGWPE to be a "Sound Card Packet Engine" which removes the requirement for a TNC to be purchased. AGWPE is free, PE Pro is trial-ware.

- TNC, or use your sound card. I use an Elcom Micro USB TNC+ and don't really know much about using the sound card setup other than that you can do it.

So, at this point, start at the bottom and work your way up:

- Tune your radio to the APRS frequency (2m) 144.390. It is at this point that you wish you bought a dual band radio so you can have one side for talking and one for APRS.

- Set the radio up for digital packet use. You'll have to dig around your manual for this one. I *think* that you can skip this step if you use the Soundcard packet as it does this in software. I'm probably wrong on that though. I really only know my setup. I have an ICOM 2720H (New one w/o the problems commonly attributed to this radio).

- Make the cable you need that goes from the TNC to the radio. If you are making a soundcard packet cable you'll need to get directions on how to do this from their website.

- Plug one end of the cable into the digital out of the radio and the other end into the Elcom TNC.

- Plug the USB cable from the TNC into the laptop.

- Install Packet Engine Pro. Tell it about the TNC you just connected.

- Test that the PE Pro, the TNC, and the radio all work by using a simple program to see if you are *hearing* APRS packets. APRS looks kinda like NMEA0183 does. It is plain ASCII text and even kinda makes sense when you see it scrolling by. I forget which program I used to do this.

- Install one of the APRS programs. OziAPRS is fairly quirky. UIView seems to be one of the easier programs to setup, but to be honest I haven't found one that I like using yet. Simply put, they are all too complicated... kinda geeky with so many features crammed into a single small program that you can't figure out how to use it. This is why I'm going to write a plugin for Overland Navigator to do APRS.

[sdlsatcom]

i'm a big fan of the tinytrak, it doesn't require a computer, simple to hook up and hide in the dash. The downfall is that it is one way, that is it will only send aprs data not recieve it

radio<====Tinytrak<====gps