Another Android APRS tracking app that is very simple

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ksaves2

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I saw a post about the W2aprs app: https://www.qsl.net/ja7ude/SmartPhone/w2aprs/indexe.html
and the OSM version that allows one to download the cacheable OSM maps for offline use: https://www.qsl.net/ja7ude/SmartPhone/w2aprs_osm/indexe.html

I put the OSM version in my Blu phone (See my post about GPS Rocket Locator) and this thing is about the easiest APRS tracking program out there.
Doesn't have a bunch of bells and whistles, doesn't/won't work with the APRS-IS system directly, but will track ones APRS rockets in a very simple
fashion. The one website shows a wired link with a variety of radios but this is supposed to via Bluetooth if no USB serial device is detected.
This means a Mobilinkd TNC should work.

One simply puts in a callsign. Can use \O for a rocket icon. Check "show my waypoint and track my position". Simple, down and dirty.

I haven't tested it out completely but for a new to APRS tracking flier this shows promise at being the easiest program to get up and tracking.

A person can have both versions on the same device. The one that can cache OSM maps and the one that uses internet, online maps. Kurt
 
Well another dead end. Bonded a Mobilinkd TNC to a Blu Android phone and W2APRS didn't work. Might be the Blu Android phone at fault although
APRSDroid worked fine. Kurt
 
Thanks for the info and heads up, Kurt. Keep up the good work.
 
Thanks for the info and heads up, Kurt. Keep up the good work.

Shoot, Always trying to find something simpler but struck out again here. I tried the W2APRS OSM in my "old" reliable Nexus 7 2013 along with the B/T
Mobilinkd TNC and no dice there either. The author said he was out of the development side of things so unless one want to do a direct wire between a D72a or D74a this program is not so workable.

Only "easy" live Android APRS tracking program is APRS Droid. I've found position accuracy depends upon the GPS chipsets used in the receive station (phone or Android tablet) and the GPS chipset in the tracker. Jim Hendriksen's advice of putting a beeper or sound device on the harness is a good idea no matter what
tracking is used. Ideally one would like to see their icons converge and have the rocket "right there" when picking it up.

I found out the hard way in a no till cornfield with black dirt and a 38mm minimum diameter rocket. Chute didn't completely deploy out of a chute release device and I had a signal with the rocket on the ground. Couldn't see it but a strong position was coming in and was plotted on the APRSIS32 app I had on a Windows tablet. I was using the NMEA based EggFinder and disconnected the patch antenna and screwed on a handheld 900Mhz Yagi antenna to the LCD receiver. I just walked a short distance in and the signal was received again. I got up to the "rocket" icon in a short time and no rocket seen!! Sheesh, what the heck. Booming signal coming in, I should be "right there" and nothing. Well stupidhead realized he needed to "zoom in" on the map. Once I did that, I was brought to the rocket shortly thereafter. The rocket was made out of black tubing and the black dirt that constituted the ground along with the corn stubble camouflaged the rocket.
Lime green chute didn't make it out of the chute protector unfortunately but the rocket was unharmed.

I learned that point right away to make sure I get the right zoom level for close in tracking. Like using an attenuator for RDF to maintain directionality of the bearing signal.

APRSIS32 can be hacked for NMEA tracker use by running two instances of APRSIS32 and of course, if one is running an APRS tracker like a BeelineGPS,
a single open instance can track on a map the Beeline GPS.

Any Ham radio person who runs Beeline GPS units could get APRSIS32 on to a tablet and track in the field. Can use a Bluetooth TNC or a direct wire connection to
a D72/D74a. Kurt
 
Kurt,

I'm a ham, but haven't done a lot with APRS other than sending a few messages through the ISS. What do you mean by a Bluetooth TNC? Can you recommend a specific model that would work well with the D72A? I plan on using that HT for my efforts as well.

73,

Les Rayburn, N1LF
 
Kurt,

I'm a ham, but haven't done a lot with APRS other than sending a few messages through the ISS. What do you mean by a Bluetooth TNC? Can you recommend a specific model that would work well with the D72A? I plan on using that HT for my efforts as well.

73,

Les Rayburn, N1LF

You don't need a TNC Les because the D72A can output the positions through the USB port and if desired, via the socket serial port where a cable can be plugged in for off loading of Waypoints. The TNC I refer to is the Mobilinkd which one can use with any H/T: https://www.mobilinkd.com/tnc2/ You don't need it.

The D72a can be plugged into a Windows tablet via USB and just about any APRS tracking program can be used to get your rocket on a map.
If you don't want to use a tablet, get a serial cable like this: https://www.gpsgeek.com/products/in...h-d7a-tm-d700a-aprs-to-garmin-4-pin-round-gps for a round port Garmin 60Cs or CsX which can be had used on ebay and open source maps can be used: https://garmin.openstreetmap.nl/ which are free.
Or use this cable: https://www.gpsgeek.com/products/in...-aprs-to-garmin-etrex-emap-geko-gps-receivers
to use with a very cheap Legend: https://www.ebay.com/itm/Garmin-eTr...185239?hash=item1a2616e897:g:i6IAAOSwdGFYqPH4
The Legend is very basic but I recall it allows basic point to point navigation to the rocket. The 60Cs(X) is a prettier display.

With this setup, you have a secure one wire connection to the handheld mapping GPS that tracks in realtime. You really can't save any of the data from the flight but it is a full featured mapping tracker I've used for years. Oh yeah, you can go home and download tracks with the Garmin software but you have to remember to change the Garmin communication protocol to "Garmin" or it won't work The handheld mapping Garmin GPS units are designed to be readable in sunlight whereas a computer
screen needs to be buried in a box to prevent glare. It can be done though. When I want something easy to carry without having to do a timely setup, this is system I use. One can tell the mapping GPS to "navigate to" the rocket waypoint and it will compute a navigation solution in realtime during the flight.
Once the rocket is down, it will take you to the last known position. If you don't get any readings once the rocket is out of range, I open the squelch from time to time on my D72 and if I can hear a "scratchy" APRS brrrrrraaaaapppp, I know I' be within range soon to decode a valid position.

Look in your D72A manual about connecting up an external GPS unit. You have to select that the waypoints are being sent to the jack and the Garmin 60Cs(X) has to have the communication parameters set up for NMEA in/out 4800bps and the D72A needs to have the port speed set for 4800bps too. Once that is done and you select external GPS on the D72A, it will use the Garmin for your local position which of course you can see on the map and it will display the rocket on the map. You can select the icon that gets displayed on the map as the Garmin doesn't generally display APRS icons. You can set your D72A to display the APRS altitude with the rocker switch so you know
how high MSL and your map for position. You can also scroll to different screens on the 60Cs(X) to a Heading Situation Indicator that will
give you a bearing to follow with an arrow and it will also tell you how long it will take you to get to the rocket position.

Ten years ago this was just about the only portable way to GPS track but cost like close to $1000.00 with a D7A(g). Now the costs have come down with used equipment and it's a very nice way to track on a map in hand. I don't recommend buying a used D7A(g) as the units are so old I have two of them that the oscillators have gone out of spec and the receive frequencies are no longer accurate. They're deaf with lousy range for APRS tracking.

Practice getting your orientation out in the field as once your rocket is out of sight, the map can give you the direction to look to try to
get a visual on the descending rocket and the APRS altitude can give you an idea when your main chute event is to occur.
I call out direction and you'd be amazed people are expecting to see the rocket coming in based on wind groundspeed and the
winds aloft take the rocket in another direction. I've had you yell out to turn 180 degrees from where they are expecting the rocket to
come in. That's the nice thing about GPS tracking, one can get an idea what the rocket is doing in "out of sight land".

Glare is the big nemesis of tracking on tablets and laptops. Large laptops are hard to carry out in the field. They can be usable if
one is interested in recording data for later easier review and relegate it to a base station whereas one uses a hand held solution
to go recover the rocket. Kurt
 
If there was a smoke bomb that would not catch anything on fire, then ignite, turn on whatever on impact. Then look for the smoke.
I know dumb idea but when I was a kid 50+ years ago working for Dad in his gas station, I had the idea to put bottled water in the coke machine, but we all decided no one would buy water.............
 
I believe there are some "cold smoke" possibilities out there where the device doesn't spread flame and has a highly insulated casing. Problem is, no guarantee and one would have to
have some sort of sealed ignition device to start the smoke without starting a fire in the process. Altimeter could be rigged to do it. Especially one that perhaps activates a beeper circuit after the rocket is down.

Still smoke might not be that much help if out of sight a couple of miles away. Kurt
 
I`ve tested as an employer, and wanted to know what employees are doing during working hours tracking the phone with the tracker's https://www.hoverwatch.com, this is what I found. In this case, I set up a special corporate mobile phone with GPS function, and activated the program for tracking the phone in it.
So the monitoring program for tracking the phone shows, in fact, where exactly employees are in working hours.
So this is all that I had to apply from trackers in practice. But the functionality is essentially the same ...I suppose this can help
 
This app is really helpful for rocket enthusiast like me. I just hope it will work just to any design.
 
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