RF trackers

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dhkaiser

Well-Known Member
After loosing a rocket with a GPS tracker, (recovered later, battery failure) and reading of others loosing GPS tracked rockets I wish to look into RF beacon trackers. I'm not sure I wish to get the SW radio license so are there any that do not require a license?

Which RF trackers are being used today by TRF'ers? What kind of $are we talking? Is there such a thing as works out of the box, ie plug and play? blackbrandt That Darn College Student You're in the same situation as me. I will be watching this thread. ksaves2 Lifetime Supporter TRF Lifetime Supporter Most of the commercial setups for RDF in the "unlicensed" category are pretty costly. Was the impetus for me to get a Ham Radio license as the cost of RDF and APRS/GPS was a bit cheaper than the "unlicensed" trackers. The earlier Com-Spec and Walston trackers on 200Mhz in the Wildlife band actually violated FCC rules that limited bird trackers by statute to 30mW. The old ones were 50mW and actually performed quite well. One can check these sites for prices: https://marshallradio.com/marshall-radio-telemetry-american-falconry https://www.radiotracking.com/ Wildman sells a system: https://www.wildmanrocketry.com/ShowProducts.aspx?Class=834&Sub=836&Sub1=837 and https://www.wildmanrocketry.com/ShowProducts.aspx?Class=834&Sub=836&Sub1=838 If one takes the trouble to get a Ham Radio license it will open up some other options some of which can be more economical. Plus in the process of learning to take the license test and radio theory, one will gain skills and knowledge to help with RDF tracking. Things like power output, propagation, yagi antennas and the need for signal attenuation will be apparent in the literature. Beeline for instance has RDF trackers both low and high powered: https://www.bigredbee.com/zc139/index.php?main_page=product_info&cPath=65&products_id=180 https://www.bigredbee.com/zc139/index.php?main_page=product_info&cPath=65&products_id=181 Whatever one does, don't get a ham license, buy a falcon tracker and expect a Ham handitalkie to be able to "hear" the tracker. (Don't ask me how I know.) The makers of those devices tweak the modulation scheme so "their" receivers are optimized to receive "their" signals. That said an all-mode receive Kenwood Th-F6A can "hear" these signals on 1.25M and 70cm bands but I've never tried to track a flown device with it. So, RDF may not end up to be "cheap" in the end. Hopefully, Jim Hendricksen will comment as he's done a lot of RDF work in the past as that was the only thing easily available. The Ham boys had APRS ten years ago but the price of admission was still pretty high. RDF was certainly had for cheaper on the Ham side than commercial side. Kurt Savegnago Last edited: ttabbal Well-Known Member I've used a Beeline RDF. It works quite well, but requires some time learning how to use it properly. It's not quite as easy as GPS, but it's not that hard. I just wouldn't want someone unfamiliar with them to be trying to learn under pressure with a lost project out there. There's lots of info out there about ham "fox hunting" to get you started. Then have someone drive off and hide it from you, see if you can find them. dhkaiser Well-Known Member Thanks Kurt! I actually have experience radio tracking birds with a yagi antenna. I have a Alinco DJ-X11 I wonder if I could use it? ksaves2 Lifetime Supporter TRF Lifetime Supporter Thanks Kurt! I actually have experience radio tracking birds with a yagi antenna. I have a Alinco DJ-X11 I wonder if I could use it? Sure you could listen all you want with that. The Beeline RDF stuff is FM and any H/T that does 70cm can work especially if it has a true signal strength meter. Need the Ham ticket to operate the transmitter though. If you want to use the Alinco for the bird trackers, get a Yagi, an attenuator and track alongside a person who has the commercial receiver and see how the DJ-X11 performs. Kurt ksaves2 Lifetime Supporter TRF Lifetime Supporter I've used a Beeline RDF. It works quite well, but requires some time learning how to use it properly. It's not quite as easy as GPS, but it's not that hard. I just wouldn't want someone unfamiliar with them to be trying to learn under pressure with a lost project out there. There's lots of info out there about ham "fox hunting" to get you started. Then have someone drive off and hide it from you, see if you can find them. Again to be clear, one must possess a Technician's license minimum for the Beeline stuff except the 900Mhz GPS tracker. Kurt warnerr Lifetime Supporter TRF Lifetime Supporter really great advice being given here. It is really worth the hassle getting a technicians lisc and it opend doors to lots of possibilities. I started with Comspect rdf tracker and have become very comfortable tracking with it. I too learned the hard way that signal is tweaked for their receiver. That was solved by buying BigRedBee 70cm transmitters- so cool to hear your lisc and your own custom message transmitted from the rocket. I run Eggfinder for gps and still include rdf on all my high altitude flights. For my L3 being super paranoid and wanting to compare products I sent it up with Bigredbee, Comspec,Eggfinder. Drove right to it and back at pad in 15 minutes after a 14k flight! Gps is great- but my go to backup is still rdf. mpitfield Moderator Staff member TRF Lifetime Supporter Global Mod My typical setup is a G10 sled in the nosecone with a TeleGPS powered by a 1S 850mAh LiPo with a full charge of 4.2 volts on one side and a Com-Spec AT-2B on the other side. The TeleGPS is fastened to the board and I zip-tie both vertically and horizontally the LiPo, with strain relief. The AT-2B is zip-tied to the other side of the board antenna up, and I use a fresh CR2032 battery with each launch event. I did a bit of ground testing to confirm that the GPS and RDF technologies did not interfere with one another in any unforeseen manner, even though they are well away from each other on the bands. When tracking, I regularly use both the GPS for last known, then if I can't pick it up again I have always been able to ping it using RDF. This has always been comforting when searching because I don't just have to rely on last known. I know the rocket is still there because the RDF tells me it is, so I just keep searching; usually with more and more expletives the longer the search takes. Bottom line I am not going for any records, except personal ones, so if it fits I use it. Last edited: michigander Well-Known Member Tech license is great just for education and not really that hard to get Blackleaf99 You can choose your behavior, not your emotions. Lots of very different systems are mentioned here. Is anyone able to summarize a table with name/difficulty/cost info ? Especially the cost info is of interest to those of us who are unfamiliar. Buckeye Well-Known Member TRF Supporter First redundant altimeters, now redundant trackers. Good time to be in the electronics business! $$:clap:$$ I guess I am old school - one altimeter and one GPS tracker in my rockets. The few mishaps I have had were all user error. I use the BRB900, and it is a nice, sturdy little package assembled by a professional (ie, not me). RF TXs are even more bomb-proof. ksaves2 Lifetime Supporter TRF Lifetime Supporter Lots of very different systems are mentioned here. Is anyone able to summarize a table with name/difficulty/cost info ? Especially the cost info is of interest to those of us who are unfamiliar. Simple. EggTimer products are the heroin-ware that gets one hooked and they're all the others. All unlicensed RDF trackers setups start about$500.00 on up. Ham stuff is cheaper but one needs to do some studying (which is good for you)
to be effective. You pick your  and there's your choice.

I forgot Byonics for ham stuff too but it's strictly DIY. https://www.byonics.com/mf I found the APRS transmitters only provided 5V for the GPS chipset so a VR has to be used with the new GPS units out there. Also kind of large devices
Though if one wants to put up a 5 watt tracker, they have one.

The AP510 is on-a-shoestring ham APRS tracker. 1.1 watts but large. I saw a fellow posted in TRF he loves his for large rockets. Very high learning curve one should peruse the yahoo group before considering. SirfIV not valid for altitude records but it will store a track on a micro SD card. https://www.sainsonic.com/ap510-apr...th-thermometer-tf-card-support-aprsdroid.html OMGosh, AP510 used to be $125.00 and now it's under a hundred. Get two and have a send an receive pair to pair with a B/T device and have a mapping tracker for$200.00. Only issue is very high learning curve and ham license required along with a larger rocket to fly. Kurt

Andrew_ASC

I’m new to RDF tracking. After acquiring a ham ticket last year for two school project launches with TeleGPS. I decided I wanted to learn RF tracking on a scratchbuild 24mm MD. So far I’ve spent about $600-700 on just the following items. -Yaseu VX-6R (Ham handheld radio with worthwhile signal meter) -Teledongle starter pack -Telemini V3 -Charger V2 plus extra lipos -Arrow Antenna 440-5 Yagi -4MHz Arrow offset fox hunt attenuator -Sma to BNC 3ft cable and BNC to BNC 3ft cable. That’s a basic plug and play setup list. If your into soldering you might save more. And making your own yagi. Now if I can figure out how to use this crap I’ll be good to go. Already have a TeleGPS and it seems so much more user friendly. You don’t get a nice long user manual with the RDF devices. So I’m digging up all the RF and RDF old threads on TRF lol. Plus there’s a lot of new techniques to learn. You follow a radio beam to the transmitter basically. But you sweep for it using the directional antenna yagi until you get too close that the signal overpowers the handheld radio and then you attenuate the signal more so you can direction find under closure of 150 ft. The good news is I’ll be set for high altitude L2 tracking when I get there. ksaves2 Lifetime Supporter TRF Lifetime Supporter Andrew, In days of old it was$1000.00 or more to do GPS tracking. There was no Altus stuff available. Just a $325.00 Beeline GPS, a Kenwood D7A and later the D7A(g) ~$400.00 and a Garmin 60Cs which was three hundred and sump'ting dollars. Plus whatever laptop one could haul to the launch site
and run down the batteries in 45 minutes! Oh yeah, Arrow antennas was around back then so add in a Yagi from them.
I GPS tracked some modest rockets at MidWest Power before 2010 and in spite of me talking it up, nobody gave two sheets to the breeze.
RDF is workable but you have to keep trying to acquire a bearing from lift-off to touchdown. The final bearing before LOS (loss of signal) is most
important so one knows which direction to proceed and hope the ground footprint is large enough so one can home in once they get out there.
Best of luck, Kurt

ksaves2

Be careful with old D7's. I have two of them where the receive frequencies are off and totally unusable for tracking and not worth getting them fixed. The TNC chip dies in them too and when the TNC component went out of production,
KW was blind sided and didn't have a replacement ready to sell. Was a long 2 year dry spell before the D-72A came out. The Yaesu VX-8R was a piece o' garbage though the VX-8GR worked good and one could get the waypoint/stations out of the
unit using the same cable as was used for the D7's and D72A. It's ashame the GR went out of production as it's mapping tracking abilities were on par with the D72 even though "full access" to the TNC wasn't there.
I thought it was a good entry level mapping tracker for an APRS flier and it was cheaper than the '72 Kurt

Andrew_ASC

UTC SEDS 2017 3rd/ SEDS 2018 1st
Kurt dang it.... you had me curious enough to tune up a Chinese satellite beacon as it flew over. I actually heard it beep three times on a stock VX-6R. It was XW-2A.

spence

Well-Known Member
I am trying the following:

Cheap $25 baefeng ham handheld Tnc. About$50
Old android phone from tge bones pile...$0 For transmitter I am using this picoaprs ham https://www.db1nto.de/index_en.html Picked it up for about$200

The transmitter sends GPS beacons on the APRS frequency 144.39 HZ

The handheld tunes to that freq and i use alrsdroid app to map it.

Added benefit in overall range if a digipeter is nearby. In that case, range can be more than you would ever need. 50 miles+.

This is just an experiment...curious if i can get it to work. In theory its a good setup.

GPS has two flaws. For LOS comm back to receiver, getting more than a couple of miles is tough....earth curvature And stuff in between,

Next you likely loss signal why the rocket is 150ft+ from the ground.

If it is drifting at 10fps, in 10 sec , thats 100 feet in any direction. Thats a 200 foot circle. Around 30,000 square feet.

My main fool proof method is Comspec RDF... even with LOS , the signal reflections work in your favor. I will use this also in my APRS test rocket.