GPS tracking with "heavy iron" of olden days

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Well-Known Member
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Nov 25, 2009
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Central Illinois
In my early days of flying, I lusted after a GPS tracker right off the bat after losing some smaller projects. I invested in an ARTS II deployment altimeter (still have it and lightly used) and wanted the unlicensed GPS tracker.
The price was a bit steep and I went the Ham route but to get the rocket track on a map-in-hand took $1000 investment anyways.

Anywho, an ARTS GPS tracker came up forsale for less than an EggFinder setup so I sprung for it. (Thanks Scott)


The GPS tracking system is sort of a cross between and EggFinder and an EggFinder TRS. With the ART II deployment altimeter attached to the GPS tracker board and the DIP switch in the ARTS position, the tracker sends altimeter and tracking data to the receiver that must be decoded using the RadioRx software. Incidentally, I was able to get the software to load on a Winbook Tablet TW801 with a locked down version of Windows 8.1 on it. The tablet downloaded some sort of a NTVDM or something or other driver and the program runs though I haven't mounted the altimeter on the tracking board yet.

With the DIP switch in the GPS position the tracker is a stand alone GPS tracker and the ARTS doesn't need to be attached to the board. The power output of the device is 100mW so it's on par with an EggFinder. I believe a different
mode of decoding is used on the receive end.

When I purchased the device, I saw from the pictures that a GPS antenna was lacking but I had several with MCX connectors so I was able to fire up the device right away. I have one GPS antenna with a short lead cable and quite interestingly it doesn't lock as many satellites indoors. The MCX amplified antennas used as external antennas on Garmin GPS devices have long cabling and I learned online that the long cable is tuned for the particular antenna and shortening the cable will degrade the performance! It is recommended to fold back the cabling into a something that resembles a shank of rope. With this in mind one would best use a nosecone mount in a long 4" diameter nosecone. Oh, the antenna with the long cable locks 7 - 8 satellites indoors. The board is serial number 28 so it's first generation and I suspect probably a Sirf III chipset. There was a second generation unit made but I don't know
if it made it to market or many units were sold. There was a picture posted on TRF that showed a serial number like 68.

I fired up the tracker upstairs and connected the receiver with a serial/USB converter and easily plotted the positions on a Linux box running Xastir. I then remembered I had this B/T serial "dongle thingie" I bought years ago and dug it out, set the speed to 9600 and was able to pair it with the laptop. That's what you see in that photo above. I had to pair it first, then turn on the receiver with the positions coming in to get it to work properly. That dongle needs external power so hence the power cable one sees hanging off the device. Nonetheless, there were live positions coming in and plotted on the map.

I then used an Android device and try if I may, I couldn't get the "GPS Rocket Locator" program to recognize the data stream from the dongle but since I have my Android device set to "allow mock GPS locations" I was able to select the B/T dongle, fire up the "Bluetooth GPS" Android program and by golly the position was placed on a google map very accurately albeit that program said only 4 satellites were locked. That was weird because the accuracy looked "too good" on the map to be just 4 satellites. I shutdown that program and fired up another Android app "Bluetooth GPS Provider" and it showed 7 to 8 satellites being tracked.

Sooooooooo.................. I took out the four screws on the ARTS receiver case and looked around inside. Looks pretty simple and I see the two traces for the Tx/Rcv lines to the DB9 serial connector. That's the thing that B/T
dongle is hanging off. The next step is to get a simple voltage 5V regulator board (about a buck or so on Epay) Wire up an HC-06 Bluetooth board and see what transpires. I'll use wire sockets for the single lines so if I switch them, no harm will be done and I can just correct the connection. If it works, just install an on-off switch for the 5v voltage regulator so it's "off" when I want it to be off and have at it.

I did use that B/T serial dongle setup with some Windows tracking programs and they connected fine and decoded the strings off the receiver perfectly.

This is sorta like an EggFinder circa 2006-2007. Advantages: Can be an independent tracker or with the ARTS II attached, a fuller featured live telemetry download ability. Disadvantages: Size but what the heck, the date on the
board says 2005 so it had to use the technology available then. Required to use the RadioRx software if one wanted to monitor the ARTS II deployment altimeter in real time. That is not so much a problem as I was able to get
the program into an 8" Winbook tablet TW801. In the old days took a laptop with a serial port or USB/serial connector. Oh, no 64bit driver for the RadioRx program either so one is stuck there.

Would be interesting if the HC-06 pairs and perhaps works with the Android app "GPS Rocket Locator".

Oh, did anyone purchase the second generation iteration of this tracking system and fly it? Kurt

Have tried to get an HC-06 BT module to work and can get it paired but only gibberish comes across a serial connection. I do have the port speeds set at 9600 and that IOGear B/T dongle out that serial port of the ARTS receiver in the picture above works perfectly.

Could it be it connects as a Null modem and how would I be able to pull that off with an HC-06 module?

The other thing if might be is I might have to attach the receive line on the DB9 socket to the HC-06 module as there might be some timing issues without both lines connected. The ARTS does have two way communication wirelessly with the ARTSII
when the ARTS II is attached to the board. Anyone get the ARTS GPS receiver to work with a B/T module outside of the dongle shown?