How about receiving APRS in flight?

Davepar · #1 03-11-2008, 07:49 PM

Ok. Tracking is now old hat. (Or it will be by the time I get my system going next week.) What do we need to receive the APRS packets in flight and display them on a screen? We can locate our buddies in the air.

MattSR · #2 03-11-2008, 08:36 PM

Generally speaking a PC and internet connection would be needed in your plane....

it may be possible to use a receiver in your plane to decode nearby stations, however im not sure if this has been done before and it would be limited in usedue it it not being connected to the wider APRS network.

Cheers,
Matt

petehowell · #3 03-11-2008, 08:42 PM

The new tinytrack4 will do it, I think. It might even display targets on your GPS. You would need a hand held radio that will transmit and receive on 144.39 to make this work.

http://www.byonics.com/tinytrak4/

I'll see if Allen will join the thread to explain. The details are beyond me.

PaigeHoffart · #4 03-11-2008, 09:31 PM

Keep in mind that you will hear every ground station within 100-200NM. I think the chances for interference are pretty high. I'd probably grab a handheld and listen to 144.39 airborne before I shelled out the bucks for a TinyTrack4. Having said that, if you use it on a discrete frequency it could be a poor man's ADSB.

Paige

jrsites · #5 03-11-2008, 09:45 PM

Quote:

Originally Posted by petehowell

You would need a hand held radio that will transmit and receive on 144.39 to make this work.

If you can find a used one of these (Vertex Standard VXA-700), you'd be in good shape. Small, handheld NAV/COM with a 2 Meter amateur band transceiver built in. Looks like the newest version, the VXA-710, doesn't include the 2M transceiver.

sonex293 · #6 03-12-2008, 05:39 AM

Allen has mentioned on other forums that he is working on a MicroTrak version of the TT4 unit with TX/RX capability. I'm sure he'll correct me if I'm wrong, but I thought it was going to be an 8W or 10W version. Just get a UMPC with the maps installed and you should be able to see all packets you can "hear".

--
Michael
KB4LFH

Lycosaurus · #7 03-12-2008, 05:57 AM

Quote:

Originally Posted by Davepar

Ok. Tracking is now old hat. (Or it will be by the time I get my system going next week.) What do we need to receive the APRS packets in flight and display them on a screen? We can locate our buddies in the air.

The Kenwood TM-D700A APRS transceiver and AvMap GeoSat5 will do what you want. The handheld version of the Kenwood is the TH-D7A. This link also claims that the EKP-IV supports displaying aprs data as well .... though have not seen it in the specs. Sure would be nice.

http://nwaprs.info/d700avmapgeosatcombo.htm

Also, here's a pdf document reviewing the AvMap G5 for GPRS use:

http://www.geosat.us/AvMapG5QST.pdf

I have a friend who uses the EKP-IV Pro and TH-D7A for CAP type operations in Canada. I'll see what he has to say about the EKP-IV tracking aprs.

Edit: April 9

My friend says his Avmap ekp-IV will not show a track of other stations, but rather, the present (or last transmitted) position of the other aprs devices.

Joe · #8 03-12-2008, 07:08 AM

Quote:

Originally Posted by Davepar

Ok. Tracking is now old hat. (Or it will be by the time I get my system going next week.) What do we need to receive the APRS packets in flight and display them on a screen? We can locate our buddies in the air.

As has been pointed out by others, the Kenwood handheld (and mobile) radios have the ability to display as well as send packets. Last weekend I rode to the Puyallup (WA) hamfest with with KE7KV in his Kenwood HT/AvMap GPS equipped vehicle. With some effort he was able to scroll through a list of stations received on the radio's display. Although he was able to put "target stations" over the moving map on the GPS screen, it seemed like it took an awful lot of keystrokes (some of them on an accessory keyboard he had on a RAM mount) and I decided it was not for me while flying.

On the other hand, Karl Gross, N7MXO-7, has a Kenwood/Garmin setup in his Mooney and once when he heard me talking with Center, he was able to track me while airborne. I'm convinced he could have flown an effective intercept with that setup.

AFAIK, the Kenwood radios are the only "off the shelf" general-purpose solutions right now but the TinyTrak4 with some sort of display may be just the thing in the future.

--
Joe, K7JD

VHS · #9 03-12-2008, 08:19 AM

Bi-directional tracking is a feature that works well with the Kenwood Products. I have a Kenwood TH-D7 and an Avmap GPS receiver that I use for a quick and dirty portable APRS monitoring station. A post above suggested that monitoring all the local transmissions would be overwhelming, but effectively, you would only be aware of those stations that are transmitting on the area of the GPS map-screen you are currently viewing.

The downside to the Kenwood solutions are these: Cost? In excess of $1000.00 using the handheld Kenwood and the Avmap display GPS. Reliability? My Kenwood has died on the bench a couple of times. I would not expect rough use to help much. Many SAR people told me that they gave up on the TH-D7 for just that reason. The mobile radio is more robust, and more expensive. Complexity? If you have trouble programming a Micro-Trak forget about programming a TH-D7!

There are other options. The Byonics TT4 will connect to a hand-held or mobile radio and provide bidirectional tracking with compatible GPS receivers. ( Serial NMEA receivers that accept waypoint uploads- I think that Byon has a list) There are a few companies making competing products in varying stages of development. These are available right now from Byonics. (www.byonics.com)

I am working on developing an integrated product using the Byonics TT4 for a "brain" and a Micro-Trak transceiver. The first product release will be a fixed channel (144.390-the North American APRS channel) transceiver with 8-10 Watts output. The Micro-Trak IV will be able to run any software the TT4 can, so things like airborne digipeating, advanced telemetry capabilities, etc. will be possible. This will (eventually) include sending and receiving airborne E-mail through the APRS network, which as you know is connected to the internet through "I-Gates". ( this will most likely be accomplished using a small LCD display and a mini-keyboard. No PC required)

The price has not been determined, but it is safe to say that it will be more expensive than a Micro-trak 300....

The next generation Micro-Trak TT4 unit will have advanced capabilities, including frequency agility, voice capabilities etc. This will be of more interest to the Ham die-hard APRS guy, and foreign users, than it would be for airborne users ( I would think) since your airplanes are too small to carry a dedicated radio operator....One advantage to a programmable frequency transceiver is that you can set up a temporary system that is not linked to the internet ( away from prying eyes) and will allow you to send many more position reports without conflicting with the main APRS frequency.

Allen R. Lord
VHS Products

sonex293 · #10 03-12-2008, 11:30 AM

Thanks for the update Allen!

--
Michael
KB4LFH..
Kilo Bravo 4 Low Flying Ham!