Just received my "wayward" TeleGPS from Keith and got it programmed with the 1.6 version on my linux laptop no sweat. I don't have the Dongle and am going to be primarily using an APRS rig, a D72A interfaced to a Garmin 60Cs. That setup is easier to carry than a laptop to carry pedestrian portable out for a recovery. I put everything outside on Sunday for a test and turned it on and let all the units, (the 60Cs and the TeleGPS) get satellite fixes and settle down after a half an hour. I'll be doggone that I couldn't get better than about 95 foot accuracy and many times > 150' error distancewhen using this setup. I don't know if the compressed packets are the issue or what. Also, I was able to scroll to the altitude and bearingfeature on the D72A and nothing was recorded there even with packets coming in. The lat/long was seen of the TeleGPS just fine and wasa bit "off" compared to the Garmin. Standing near the TeleGPS with 9-11 satellite fix and 95 to 100' off could make for some difficult recoveries. I thought something was weird here. Soooooo...... I pulled out a Mobilnkd TNC and plugged it into another H/T (or I could have used the D72A left in APRS mode as the Mobilnkd simply plugs into the earphone jack and microphone jack) The Mobilnkd is a B/T KISS TNC so I bonded it to my Nexus 7 Flo 2013 that has the OSM version (self-contained maps) of APRSDroid on it. Fired up the TeleGPS and let things settle down. I began seeing 30' and less than 30' correspondence (ie. more accuracy) with that setup pertaining to both devices positions. Anyone else use an APRS rig and interfaced Garmin GPS to track? Do you have different observations than me? I only did the one session so that doesn't makea definitive "trial" of course. APRSDroid would be a reasonable fallback for me but it's klutzy to track with. One has to "transmit" an APRS packet on frequency to get their position to "move" on the map. It you don't do that, your station icon just sits there. There is of course no datum tracking line but since I had flown airplanes in the past, I don't have trouble looking at a map and figuring out the spatial orientation. An interesting observation I made at a recent launch is a fellow was flying a Beeline GPS with a 60CsX/D72a, in fact I had told him about the interface cable for real time tracking at a launch in the past. He had a heck of a time manually inputting the lat/long into his handheld. He was ecstatic when I told him it could be done automatically with a $25.00 cable. Well at the last launch, he had his receive station and I had mine tuned to his frequency (I like the practice any chance I get) and he launched to over 8k. I was reading off the altitude from my D72A and keeping tabs on my 60Cs mapping GPS of the rockets position. I noticed the rocket was drifting overhead, still way up there, from the northwest to the southeast. I turned to face the direction where I would expect to see the main. It was coming in at 5k and I noticed he was still facing northwest. I thought he would get oriented soon. When it got to 3500 feet, I noticed he and everyone else were still facing the northwest. I yelled at them to turn to the southeast for the expected main deployment. The rocket was far enough out there that it was unseen until the main came out as scheduled. I learned a lesson that it takes practice to read a map and get oriented. Since I soloed an aircraft at 16 and learned to navigate via dead-reckoning and the VOR range, I still had the "knack" even though I gave up flying after going to college. (Bum eyes wouldn't have let me do it for a living.) Any thoughts? My Garmin maps are up to date and I believe I have the proper Datum standard. One might ask, "Why the heck you get a TeleGPS and why didn't you just stick with a BeelineGPS?" Easy answer is, "The smaller size!" Fits in a smaller nosecone! I'm rapidly developing a liking to the TeleGPS and hope to be able to sort out the APRS/Garmintracking quirks. If not, I'll use the Mobilnkd/Nexus/HT setup and if necessary RDF yagi with attenuator to home in if necessary. Kurt Savegnago KC9LDH
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