Why Not Use This for GPS Rocket Locator Device?

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I don't do spirals
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I'm sure it has been asked before (Probably by me if I know myself correctly) But why not use one of these? It puts location right on Google Maps for you.

Drawbacks I see are

1. Needs a sim card (but cheap ones cost $60/year)
2. Must have cellular coverage at location

What am I missing?
 
First of all you have to have cell coverage. Whey my local club flies we are on the fringes and sometimes don't have reliable service.
Second make sure this device doesn't operate on 3G cell service. My daughter has similar gizmos on the collars of her dogs so if they get out of the yard she can find them. Her dog trackers use(used) 3G so they no longer work, and the new ones that use current cell service are much more expensive.

Actually I have a Garmin Inreach Mini that would do the trick for you, but on sale they are at least $250. I use mine when I am in my Jeep in places that don't have cell service. I can set it to send my location occasionally to the satellite network and my wife can go online and see exactly where I am.
 
I read some of those reviews online they didn't get very good reviews, as one person said "just another piece of Chinese junk".
 
I found a small one that is definately 4G with GPS and Radio Triangulation (aGPS), as well as found a sim card that is data only at a one-time $5. I have no choice but to try this.
 
They work as long as your launch site as cell data. If it does not, good luck
 
I found a small one that is definately 4G with GPS and Radio Triangulation (aGPS), as well as found a sim card that is data only at a one-time $5. I have no choice but to try this.
Can you share the link to the GPS and sim card? That sounds like a great deal.
 
I found a small one that is definately 4G with GPS and Radio Triangulation (aGPS), as well as found a sim card that is data only at a one-time $5. I have no choice but to try this.
Yes, I too would love to see links for the GPS and SIM card that you found. Thanks!
 
If you want to try one of the cellular "ping" trackers, be sure it's at least LTE (G4). G2 and G3 cellular systems are either shut down or are in the process of shutting down, so if you buy one it may just be an white elephant.
 
Whew! Hefty little critter ~90g/3.2oz for the smaller one, and at 63mm/2.5” x 36mm/1.4” x 27mm/1” you’ll need a decent sized payload bay. Hopefully you’ll get some good results, looking forward to a report from the field.
I will be removing the two large magnets in the case & shave the case. My hope is to lose 30-40% of the mass & fit in a 29mm tube
 
Search around Aliexpress. There are a bunch of different units. If you're in a place with 2G still operating, I saw one 15mm wide that would fit in a BT-20. If you're good with that stuff, I'd wonder if swapping the cell bits for something compatible with 4G would be feasible? That aspect of it is pretty much a black box to me.

The smallest BT that would fit any of the 4G units I saw is a BT-55 (25mm wide PCB). But you can get one that's just the electronics and pads for soldering on all the other leads. Even one with the GPS receiver mounted remotely. Lots of options.

Just remember that the way they work (as far as I can tell) is to send their tracking data to a server in China, from where you retrieve it via their app. Which means the ChiComs are more likely than not accessing the server if not actively monitoring it. I'd be OK using it for an occasional rocket flight if their app could be downloaded from the Apple servers, but would be sure to not have power connected to it the rest of the time. And use it for much of anything else, especially anything not intermittent? Hellz to the NO.

Some of the trackers are configured to allow the unit to shut down the fuel pump of a vehicle when commanded. Give that power to a server that takes orders from the ChiComs? FNO.
 
I was not and currently am not a cyber war guy but I’ve seen what my cyberpunk brethren can do with a few keystrokes. I would save and spend the yankee dollars on a stand alone system.
 
I picked up one of the ones the OP posted about, to track my cat. I have not had time to get a SIM card to try it. I don't have much faith in expected performance, since the small size translates to small antennas and reduced RF performance. I may be surprised, but I am not expecting miracles from it. It will be fine for the cat.
 
I am currently having a simple GPS / IMEI Tracker program written for me that avoids the Chinese angle, as well as simplifies the interface - you do not need to call the tracker, trace it, set boundries, listen in, so many un needed features, I simply want to plug in the IMEI and get it shown on google maps.

Being written for both iPhone & Android.

This is fun for me - I'd love suggestions, ideas, comments.
 
You have to remember that even if you have cell coverage on the ground, you might not have it at high altitudes depending on beam patterns of the nearby cell sites vs their distance.

Eggtimer Mini TX fits (just) in an 18mm tube and needs no cellular connection. Best bang for the money IMO, TX range at least 10-15km thru the air and maybe 1km on the ground.

I've seen non-GPS arrow trackers that weigh a few grams with battery and will fit in a BT-5, but they typically have limited range of a few hundred yards and are very expensive.
 
We're hoping to shave 1mm or so off the width of the Mini in the future... it's really just a tiny bit too large for an 18mm tube. The absolute minimum that we could go would be 16mm... that's the width of the RF module (the GPS module is about 15mm wide). The mounting holes would have to change, too.
 
We're hoping to shave 1mm or so off the width of the Mini in the future... it's really just a tiny bit too large for an 18mm tube. The absolute minimum that we could go would be 16mm... that's the width of the RF module (the GPS module is about 15mm wide). The mounting holes would have to change, too.
Doo eet!
 
Only advantage I can see using a cell system tracker is one might be able to get the final recovery site of the rocket. That is of course if the GPS receiver antenna isn't facing the dirt and there is cellphone reception with the unit on the ground.
With live Rf/GPS trackers, depending on range to the receiver, one still can receive a last known position with the tracker 25 to 100 feet in the air. The rocket is usually found very close to that spot unless the wind is dragging the main chute and rocket across the ground.
Advantage to Rf/GPS units is no subscription fees and can fly whenever one wants without activating a fee.
Either system works well though. Kurt
 
I received this unit from china, plugged in a sim card, and it works flawlessly. Within 5 feet. Tracked well & fairly simple setup. Now I need to modify it by removing the (heavy) magnets & try & trim the case so I can fly it.
 
I received this unit from china, plugged in a sim card, and it works flawlessly. Within 5 feet. Tracked well & fairly simple setup. Now I need to modify it by removing the (heavy) magnets & try & trim the case so I can fly it.
Pictures of the process would be most welcome.
 
I am currently having a simple GPS / IMEI Tracker program written for me that avoids the Chinese angle, as well as simplifies the interface - you do not need to call the tracker, trace it, set boundries, listen in, so many un needed features, I simply want to plug in the IMEI and get it shown on google maps.

Being written for both iPhone & Android.

This is fun for me - I'd love suggestions, ideas, comments.

How's work going on the simple GPS Tracker program?

Will the program include velocity?

That would be great if it could tell you whether the rocket you just launched out of sight is coming in ballistic or under parachute.
 
I received this unit from china, plugged in a sim card, and it works flawlessly. Within 5 feet. Tracked well & fairly simple setup. Now I need to modify it by removing the (heavy) magnets & try & trim the case so I can fly it.
inquiring minds must know about this new gadget.
 
Actual electronics are only 25 X 50 X 5 mm Battery is the majority of mass. Removing magnets & case lowers mass by 30%.
It works on my flying field, I'll be testing it shortly.

IMG_0480.jpeg
 
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