GPS tracker that is as accessible/easy/ready to go as Jolly Logic Chute Release?

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Tramper Al

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Hi,

I am interested in being able to find my mid power models, flying on E-F-G. I'm not interested in using more powerful motors at this point.

I recently found the Jolly Logic Chute Release device, which I think will be very helpful in getting my rockets to land safely somewhat nearer to the launch pad - and thus be recoverable. I was not and am not particularly interested in working with homemade black powder charges, getting a powder license, or visiting gun shops.

By the same token, I'd like to be able to find a mid power rocket that has flown high and drifted out of sight, or even come down unobserved. But I am at this point not particularly interested in building electronics, soldering small connections, making sleds, getting a HAM license, etc.

Is there a product out there that is basically consumer-ready out of the box, to load in a payload section, that will direct the search team and allow a rocket to be found on the ground?

Thanks!
 
The BigRedBee BRB900 is an option for an unlicensed tracker that is assembled. I don't have firsthand experience - perhaps someone else can chime in.

None are going to be as easy to use as a Jolly Logic Chute release or JL Altimeter, however there are a number of excellent units available to us rocketeers.

Eggfinder and Eggfinder TRS- its a kit that requires assembly, as in soldering parts (small ones too), its the least expensive because its a kit, with a bluetooth module added it can display directly to a cellphone or computer. I have experience with the Eggfinder TRS and I really have enjoyed it so far, there is a small learning curve, the Eggfinder is easier to operate than the Eggfinder TRS (which is a Deployment Altimeter as well as GPS tracker). Conner (Conman13 here on TRF) can assemble one for a reasonable fee and test it to make sure it works properly (you buy the unit and have it shipped to Conner who then assembles it for you for said fee) which iirc is still cheaper than any of the other units listed below. No HAM license required for any Eggfinder products.

Missleworks Rtx, nearly ready to go out of the box, has a learning curve, no HAM license.

BigRedBee-excellent products with an excellent reputation, I have no experience, no HAM license as mentioned earlier.

Altus Metrum-great products, excellent reputation, again I have no experience, iirc AM products require a HAM license.

Edit: I almost forgot the coolest of them all:

Kate: darn she's expensive but wow is she cool, made by Multitronix. She's also a bit large for most MPR rockets since she requires a 54mm airframe.

Edited Edit: the Eggfinder TRS with 300mah lipo and short antenna weighs in at 70g, the Eggfinder even less. The Missleworks near the same iirc, they will fit in many E-F-G rockets, but may be marginal on some E rockets unless they are AT/CTI composite motors. As Kevin pointed out some are just plain large or heavy.
 
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Real Flight Systems - I have this one, and love it. It works out of the box, it's well engineered, and is also unlicensed 900 mhz.

Serious GPS for the serious rocketeer.

That being said, I don't know of a simple, inexpensive out of the box GPS solution suitable for mid-range rockets.
 
The BigRedBee BRB900 is an option for an unlicensed tracker that is assembled. I don't have firsthand experience - perhaps someone else can chime in.

Folks, remember OP said E-F-G rockets. Most of the stuff you mention is mighty fine but not modroc or mid-power capable. They'll weigh the rocket down so much you won't need the tracker to find it 'cause it flies so low.


Might be too big for E-F-G rockets. There are a variety of GSM trackers out there that depend on a subscription to a cell phone service and one needs reliable cell service at their launchsite. It requires a monthly fee or subscription service: https://www.giantleaprocketry.com/products/components_electronics.aspx I think with small rockets the flier will need to consider the small RDF trackers like used in falconry. The problem with these commercial solutions is that they are very pricey. The smallest GPS tracker I am aware of for rocketry is the Tele-GPS but again, that requires a ham license.

With RDF, one needs to get a good lock on an initial bearing for a completely sight unseen rocket. Holding a handheld GPS parallel that has a "sight n' go" feature parallel to the Yagi antenna might help. It's essential one gets within the ground footprint of the transmitter to lock in a new bearing after the rocket is down. If the rocket drifts way too far, one might not get a good enough initial bearing to be in a position to pick up the signal again. If the rocket
does go far, you will lose the signal once it gets lower. If you don't have a visual, you'll have to depend on your initial bearing to hopefully get you within the ground footprint.

I've had some fun with the XFM-1 transmitter which really isn't that powerful: https://www.jbgizmo.com/page30.htm Technically one is supposed to be a Ham as it's on the 2 meter ham band and the optimal antenna length is 2 feet. I am a Ham and flew one in a long Estes rocket with a 2 foot antenna on the tracker that was extended fully when the apogee main came out and a 3 element 2 meter Yagi.

There are these transmitters on the FM broadcast band: https://www.jbgizmo.com/page22-i.htm https://www.ebay.com/itm/like/322044918819?lpid=82&chn=ps&ul_noapp=true

The DIY kit 32 here: https://transmitters.tripod.com/begin.htm is three transistors.

Problem with these cheap kits is that they have a tendency to drift frequency as the battery runs down. It may shift a bit while reaching thermal stability over 15 minutes or so but then shifts at a slower rate

A less than an optimal tuned antenna length will cut the range maybe dramatically. Advantages: Cheap, can use a little transistor radio analog preferable to digital due to the observed drifting. You can tune easier with analog
Disadvantages: Be out in the boondocks so your signal won't P.O. a commercial station or listener. That's not likely with the low power but one can't be certain with these devices that drift.

If messing with modrocs, this is a cheap way to get your feet wet. I'm afraid there is no commercially available "cheap" micro GPS for the E-F-G rockets you mention. Plus any added weight of the tracker may
very well keep your rocket within sight as opposed to totally sight unseen. Ok, ok. There is the Marshall unit but you go price it: https://marshallradio.com/north-ame...ms/item/629-marshall-gps-system-north-america One grand to stick in your modroc is too rich for my taste. Possible sure but if you can afford it, you can afford to move on to HPR.:wink:

Ahhhh, I built a lot of this stuff myself while learning so developed some familiarity before getting a General Ham license and moving on. Kurt
 
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An Eggfinder TX will fit in a BT50 body tube, HK has a little 350 mAH 2S LiPo that's about 17mm x 12mm... perfect for that urge to launch something really light on a D21.

You want something smaller? Stay tuned... :wink:
 
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Thanks for the suggestions! I have looked at some of these in the past, and will look at the others now. True, it will only be the larger diameter rockets I'll be able to consider for the Chute Release anyway (maybe BT-60 and above), but with that expensive piece of hardware aboard it seems prudent to make the rocket as easy to find as is feasible.

As for the Eggtimer (which looks great), no I don't think I am necessarily looking for something smaller, by perhaps just something more finished.
 
An Eggfinder TX will fit in a BT50 body tube, HK has a little 350 mAH 2S LiPo that's about 17mm x 12mm... perfect for that urge to launch something really light on a D21.

You want something smaller? Stay tuned... :wink:
Hi cerving,
So, why not offer in-house assembly (or formally farm it out) and also sell a completed ready-to-go unit as an alternative? The assembly task (even among enthusiastic rocket builders) seems to be a stumbling block for a lot of would be purchasers, from what I have read.
 
Hi cerving,
So, why not offer in-house assembly (or formally farm it out) and also sell a completed ready-to-go unit as an alternative? The assembly task (even among enthusiastic rocket builders) seems to be a stumbling block for a lot of would be purchasers, from what I have read.

FCC etc. testing regime is fairly cost prohibitive AFAICT. A DIY kit has different requirements.

It's much the same way as some people choose to only fly FAR101 <2,000 FT: no sparkies, no hazmat, no hybrids etc.
 
I've been very lucky the last few years and have not lost any of my mid power rockets. However, I have spent a lot of time walking the fields. Last year I broke down and purchased a BRB900 for my WildChild. Out of the last 10 flights, I had one that we completely lost sight of it against an overcast sky. The wind carried it in the opposite direction from the breeze at the pad. We kept looking in the wrong direction and never saw it come down. Had it not been for the BRB900, it would have never been found.

I have the unit in a Rocketry Warehouse nose cone. The entire assembly weighs 6.3 ounces more than the stock nose cone from Wildman filled with foam. A lot of the weight is due to the fact that the RW nose cone is much heavier than the original one.
 
Hi cerving,
So, why not offer in-house assembly (or formally farm it out) and also sell a completed ready-to-go unit as an alternative? The assembly task (even among enthusiastic rocket builders) seems to be a stumbling block for a lot of would be purchasers, from what I have read.

There is someone here on the forum that assembles the Eggfinder stuff and charges a very reasonable fee to do it.
I assembled my first couple EF's but now I used Connor.
 
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There is someone here on the forum that assembles the Eggfinder stuff and charges a very reasonable fee to do it.
I assembled my first couple EF's but now I used Connor.
Thanks, I do have a note out to him.
 
I had Connor assemble my first two Eggfinders, and he does fantastic work for a very reasonable price. I can highly recommend his service, if you choose to go that route. Since then I've built four of them myself, and it gets easier each time. I had my doubts at first but it really isn't all that difficult, and I'm an old guy with glasses. It's a new skill that I've acquired, simply because I like building things (like rockets). I don't own a Jolly Logic Chute Release, but it sounds like a well engineered product and is ready to go right out of the box. Long before it was available, I had been flying high powered with dual deployment, so things like deployment charges are almost second nature to me at this point. Recovery is still the single most challenging aspect of rocketry and dual deployment of some sort is absolutely necessary when you're launching higher in anything other than perfect conditions. I've lost plenty of rockets over the years and the Eggfinder was the product I chose to go with to help me recover more of them. Buy a TX and LCD RX and have it sent to Conner for assemble. Sure you have to do some of the work yourself, like mounting and working out a tracking solution, but you won't find a better system for the price.
 
An Eggfinder TX will fit in a BT50 body tube, HK has a little 350 mAH 2S LiPo that's about 17mm x 12mm... perfect for that urge to launch something really light on a D21.

You want something smaller? Stay tuned... :wink:

Pretty please............................ Do a model on 70cm? I don't mean APRS either. Yeah I know it would take a 70cm receiver that you'd have to design but the propagation on 70cm is quite a bit better than 33cm.
There are quite a few Ham fliers out there still. Kurt
 
The RF modules are available in 70 cm, so it would be pretty easy EXCEPT that it has to somehow transmit your call sign too. For the TX, that would mean adding some circuitry, probably a processor and a multiplexer. I could do it with the TRS, except that there's no more room available in the processor's flash memory.

I'll consider making it an option for some product in the future that may have the necessary facilities to transmit a call sign.
 
The RF modules are available in 70 cm, so it would be pretty easy EXCEPT that it has to somehow transmit your call sign too. For the TX, that would mean adding some circuitry, probably a processor and a multiplexer. I could do it with the TRS, except that there's no more room available in the processor's flash memory.

I'll consider making it an option for some product in the future that may have the necessary facilities to transmit a call sign.

Yeah, That's why I mentioned it. I see the extra string in there coming in from a TRS. Have the call in there on a 70cm product and all's well with the Federal Cookie Cutters. Would be easy to confirm selling as just make sure the shipping address matches the address in the FCC callsign online database. Kurt
 
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