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Caution about tracking app "GPS Rocket Locator"

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ksaves2

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Hey,

Just a heads up on the Android app "GPS Rocket Locator". It's not an intrinsic problem
with the app itself or a danger to one's device it's simply that Google maps don't work anymore.

I received this reply from the author:

"You are right. It doesnt work anymore...
They probably changed the url for getting tiles. I dont know when i will have time to work on it. Im busy these times."

I've asked if there is a way to set the default to OSM for new installs. I'll see what he says.

If anyone has cached maps for off line use, be careful with your system because there isn't
the means to restore for now.

It was nice to see how close to a farm building or electric line or tree one's flight went but the OSM maps are adequate to plan a recovery. Sometimes it's easier to drive on road to a place where it's a shorter hike to pick up one's rocket. Kurt
 

bdureau

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well unfortunatly the software is not opensource so we cannot fix it .
It is a shame because I know Android dev and I should have been able to help
 

Steve Shannon

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If the path is stored as a string in the executable you may be able to simply use a binary editor and change it without needing source code. Of course it may be that it the code calculates a checksum to detect changes to its resources in an effort to be secure, but it's worth a shot.


Steve Shannon
 

ksaves2

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I can't help you here because I'm just a script kiddie. The author's site is here with his contact address: https://rocketlocator.com/

As he said, he's busy and doesn't know when he will be able to get at is. The Open Source Maps still cache properly and is still useful for
planning recoveries in relationship to nearby roads (for us "flatlanders") In other places, an aerial map alerts one to geographic obstructions
that may impede a recovery route. Nice to have but one can still get their rockert back nonetheless. Kurt
 

ksaves2

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It looks like this was fixed in August.
Yup,
It was fixed and documented in another thread. There were some open photomaps out there that are usable. Not the latest and greatest but certainly well enough for one to navigate around obstructions. Kurt
 

billdz

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Did the fix stop working? I just downloaded GPSRL for use with my new T3. Google Maps not working. Open Street Maps is working, but apparently no Satellite View. Is there a way to get Google Maps, or a way to get Satellite View with OSM?
Thanks,
Bill
 

ksaves2

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We're SOL concerning a photomap now. If one took the trouble to "wilfully" save the tiles, Better back them up.
The ham radio app aprsisce/32 can be hacked tor use with NMEA trackers but the learning curve is very high.
Kurt
 

ksaves2

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Can you use the maps available from https://www.webgis.com/landsat.html?
I think that's what Mr. Lynn Deffenbaugh, KJ4ERJ does with aprsisce/32. That's my preferred app for tracking the NMEA trackers with a photomap for now. Was able to download various zoomlevels to memory of the sites I fly at. Those photomaps are
a few years old (I'd guess maybe 3 to 5years on the closeup stuff) but still very serviceable for rocket flying.
Aprsisce/32 one feeds the NMEA strings in one instance to track the rocket and use a second instance to take your local GPS position and "beacon" it through an internal network to the 1st instance once every 10 seconds. Both positions get plotted on the
same map.

Except I think there might be some latency issues and I am going to get my local position on the map before launch. Shut off the internal network so the 1st instance of aprsisce/32 isn't wasting time listening for the local "beacon" and then just track the rocket while in flight.

That's what's important. Once the rocket is down, I'll fire up the 2nd instance to beacon the local position to the 1st instance a turn on the network monitoring in the 1st instance. That will get both icons, rocket and local position on the map. Sounds hard but it isn't really.

I thought some rocket positions were missed on the map due to monitoring of the network but once the rocket is down, it's not that important and both instances can be used at once.

I don't code so I don't know if GPS Rocket Locator could be modified to use the GIS tiles. I thought the code was put on Git-Hub so anyone could have a stab at it. When Francois "fixed it" the first time, I ran to a high speed link and
downloaded my preferred launchsites and local areas at various zoom levels. Took a heck of a lot of time to back up but I still got 'em. I want to try GPSRL again with them.

Alternatively, the "missed" positions from the EggFinders "could be" explained by the difficulty of decoding the positions because of the constantly changing position of the tracker antenna and hence the polarity of the radio signal
when the tracker is "flopping around" under drogue. How to get around this? As Tim Taylor said, "More horsepower, argh, argh, argh!!" Indeed higher power can overcome some of the polarity mismatch as can a more sensitive
or higher gain antenna like the patch antenna for the 900Mhz bands. I certainly noted more recovery of positions when using the "Patch on a pole": antennastick.jpg
If one can blow their main up higher like 800 to 1000 feet the antenna position generally settles down into a vertical orientation and position recovery is improved I've noted. Also a higher altitude can lead to a better propagation to some
degree and a drift pattern can be seen on the map, aprsisce/32 or GPS Rocket Locator. This can give one an idea of what direction to go if they get to the last known location and no rocket is seen.

Kurt
 

Nathan

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If the path is stored as a string in the executable you may be able to simply use a binary editor and change it without needing source code. Of course it may be that it the code calculates a checksum to detect changes to its resources in an effort to be secure, but it's worth a shot.


Steve Shannon
Ah, reminds me of the good old days when I was an assembly language programmer and used to debug programs by patching the object code in machine language.
 

dhbarr

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Ah, reminds me of the good old days when I was an assembly language programmer and used to debug programs by patching the object code in machine language.
I'm sensing a trend in your skillsets here... next up, old master engraving! :-D
 

Steve Shannon

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Ah, reminds me of the good old days when I was an assembly language programmer and used to debug programs by patching the object code in machine language.
Exactly. Twenty five years ago I bought a Micron Technology motherboard when the 486/66 first came out. It was the same motherboard that Gateway Computers used at the time, but I read that Gateway had issued an update to their BIOS that had fixed some things so of course I had to have it. I downloaded the bios patch and prepared to burn it, which was done by copying the bios code to the first sector of a floppy and booting tomfloppy. But I spotted a misspelling in the BIOS copyright notice. Two letters had been transposed, so I used a hex editor to swap them, thinking the CRC or checksum wouldn’t care. It wouldn’t boot.
Nearly panicked I went into work and used debug to prepare a new floppy (with the misspelling) and retried it. Fortunately that worked, because it was an expensive motherboard.


Steve Shannon
 

cerving

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Exactly. Twenty five years ago I bought a Micron Technology motherboard when the 486/66 first came out. It was the same motherboard that Gateway Computers used at the time, but I read that Gateway had issued an update to their BIOS that had fixed some things so of course I had to have it. I downloaded the bios patch and prepared to burn it, which was done by copying the bios code to the first sector of a floppy and booting tomfloppy. But I spotted a misspelling in the BIOS copyright notice. Two letters had been transposed, so I used a hex editor to swap them, thinking the CRC or checksum wouldn’t care. It wouldn’t boot.
Nearly panicked I went into work and used debug to prepare a new floppy (with the misspelling) and retried it. Fortunately that worked, because it was an expensive motherboard.


Steve Shannon
Back the the really good old days, there was no CRC on the object code... whatever you did stuck. Both a curse and a blessing... it did make it really easy to patch things by adding a JMP instruction and some NUL's, tacking your code to the end of the file, and ending it with a JMP back to the original "next instruction". Of course if you got it wrong you were completely foobed...
 

ksaves2

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Hmmmmmm, I had lockups with Rocket Track early on. Doesn't one have to have their tracking system up and running with good GPS locks on both ends to get
Rocket Track going? Also, does Rocket Track have any facility to download and cache maptiles for off internet use? If there is no cell phone/internet service
at a remote site, not going to be very usable. GPS Rocket Locator did develop a map caching ability and I realized google can be finicky and saved photo maptiles at
a variety of zoomlevels at the two sites I frequent. Sat at work on a weekend and batch downloaded tiles for storage. I just lift them off the device and
transfer to a new one I'm using.

I'll have to try RT again and see what happens. Have a used Nexus 6P coming with 64Gb I'm going to root and get a decent custom ROM on it starting from scratch.
I hate diddling with an established setup once I have a pile of software in running well. Sometimes the backups take forever to get going again.

Kurt
 

Handeman

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My rocket locator is working great. I downloaded the google satellite maps the first weekend I used it. I had to hit "download maps" quite a few times but now it has all the tiles for the launch site and works great.
 

ksaves2

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Ok, Decided to "lift" off the photomap tiles I batch downloaded to the mapcache from one Android device to install in another. I tried copying to a computer and then sending the tiles from the computer (both windoze and linux) to the "new" to me device
a Nexus 6P. Yeah I know about the "bootloop of death" but got a ROM on it that shutdown the four offending cores out of the eight so it's a Quad core phone now. A heck of a lot faster than the Blu phone I had and stable. Plus 64Gb on the used
market is cheap relative to a new device plus I can put custom ROMs on it to my satisfaction and have resurrected "bricked" devices using Ubuntu linux in the past.

Getting back to lifting the photomap tiles off one device and putting them on another. First off I sat at the office with a high speed internet link and willfully used GPSRL to download maptiles using the upper right pulldown (before they "went away"). I scrolled to the area of interest and hit download many times. The tiles reside in /sdcard/mapCache/google. If one wants to, they can do it with the available OSM tiles for off internet use too. They're in /sdcard/mapCache/osm.

Now getting ~600mb of maptiles into another device was a problem. The computer method, the throughput of the transfers would have taken days! Yes days! What I found worked was placing the tiles on an OTG USB stick. Problem there was they
wouldn't all fit into one directory due to partition constraints so I had to do three directories to put all the tiles in. /Nexus72012full, /Nexus72012fulla and Nexus72012fullb.

Next is easy for some devices. Use something like EF File Manager to stick the tiles into the proper directory on the new device from the USB stick. I had the problem that the stupid, rooted Nexus 6P I had couldn't reliably read the USB stick! So I fired up
TWRP (Team Win Recovery Project) by hitting "reboot recovery" and with the file manager there in TWRP was able to transfer the files to the 6p very rapidly. Like 15 minutes instead of days. I have no idea why my 6p on Lineage 15.1 couldn't
read the stick but TWRP could. Nonetheless, it might take some diddling if one has saved photomap tiles they'd like to get into another device. It's doable but one may have to be persistent.

I believe it helps if one's device is rooted but I'm a control freak. Remember, one had to have downloaded the tiles and simply using GPSRL "over the air" didn't lead to saving the tiles.

Now the Rocket Track app has an interesting interface but it is confined to being used only if live internet is available. Kurt
 
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