GPS tracking - what's your preference?

Ok, so I have a BRB GPS (70cm version) and a Kenwood TH-D7a(g) combo. Using the TNC it works great, displaying the GPS coordinates.

For actually trekking to the location, I was considering purchasing a handheld GPS unit. While I can buy a used unit on thEbay, they are still pricey.
So here's the decision I'm faciing...

I can purchase a used handheld GPS for $200 - $250, or a new unit for much more.

Or, with GPS units being relatively pricey, I could instead purchase a handheld radio with an integrated GPS, such as the Kenwood TH-D72a, or the Yaesu. It's bit more, yet it's one less thing to carry.



For those of you that do this, do the combo handheld radios with integrated GPS work well for navigating to the destination?
Or, do you prefer using a dedicated handheld GPS unit?

I initially started with a GPS, and quickly realized I only have so many hands.

More parts = more stuff to keep track of and to haul around. Because of that, I went the route of a radio with a built-in TNC and GPS (Yaesu VX-8GR).

-Kevin

What Kevin said, except that I prefer the Kenwood TH-D72.

The Kenwood will plug into the https://www.hamradio.com/detail.cfm?pid=H0-011077 moving map display. But then you're carrying two things again.


Sent from my iPad using Rocketry Forum

Yeah, makes a lot of sense, I like the idea of a single device. I guess it's time to start shopping for my next radio....

I used the same setup as you for a couple of years, the BBR with a Kenwood TH-D7a, and a separate handheld GPS. Worked great, but I also wanted one less thing to carry. Like Kevin, I went with the Yaesu VX-8GR, and have been very happy. At the time I bought mine the Yaesu was about $130 less than the Kenwood TH-D72A.

I believe the VX-8GR has been discontinued. Not sure but I think the replacement is the FT-1DR. Yaesu has raised their price and is now very close to the TH-D72A.

While people could argue Yaesu vs Kenwood all day long, one thing to keep in mind is that the menu between the D7a and the D72a is almost the same. Took me a while to learn the Yaesu menu after using Kenwoods for years.

If you do go for upgrading your GPS, you might want to think about Craigslist. You get to see and try the unit. Just bought a Garmin Dakota off of Craigslist that looked and worked like new with the forever maps for about 1/3 the cost of a new one.

Mike
N0JDB

catman001 said:

I believe the VX-8GR has been discontinued. Not sure but I think the replacement is the FT-1DR. Yaesu has raised their price and is now very close to the TH-D72A.

Click to expand...

You're correct on the Yaesu radios, at least model-wise. No clue on prices, as I haven't shopped for them for a long time.

While people could argue Yaesu vs Kenwood all day long, one thing to keep in mind is that the menu between the D7a and the D72a is almost the same. Took me a while to learn the Yaesu menu after using Kenwoods for years.

Click to expand...

I think it's ham radio's religious war. In my opinion, and based on what I've read, they're just different. I know how Yaesu does their menus, so that's what I buy - I don't use my radios enough to want to try to remember how to use two of them.

The folks I know with Kenwood radios have been very happy with them.

-Kevin

Worsaer said:

Ok, so I have a BRB GPS (70cm version) and a Kenwood TH-D7a(g) combo. Using the TNC it works great, displaying the GPS coordinates.

For actually trekking to the location, I was considering purchasing a handheld GPS unit. While I can buy a used unit on thEbay, they are still pricey.
So here's the decision I'm faciing...

I can purchase a used handheld GPS for $200 - $250, or a new unit for much more.

Or, with GPS units being relatively pricey, I could instead purchase a handheld radio with an integrated GPS, such as the Kenwood TH-D72a, or the Yaesu. It's bit more, yet it's one less thing to carry.



For those of you that do this, do the combo handheld radios with integrated GPS work well for navigating to the destination?
Or, do you prefer using a dedicated handheld GPS unit?

Click to expand...

D72a with a Garmin 60Cs. It's a very pricey combination. A Garmin 78 I believe has a round serial port. But you are looking at a hefty investment.
Let me caution you about using a used D7A(g) I have two of them and they are off frequency on 70cm and aren't usable anymore. I don't want to pay someone to realign them if they are unstable and will go out of tune. Be careful
if you are considering buying one of those used.

The nice thing about the mapping GPS is one can tell the unit to "navigate to" the rocket waypoint and it will automatically give one a datum line to the rocket. Can scroll from screen to screen to look at the map or scroll to the compass/datum line to the last known position. Some folks get by, by following the arrow on the VX8GR but now that unit is out of production and the FT1DR with a "bunch of useless to tracking" digital stuff is the substitute. A big advantage to having a handheld receiving station is if the rocket isn't "at" the last known position, your handheld station has a good chance of picking up a new packet since you are closer. If one uses a laptop for a fixed "base" station and inputs the lat/long manually to a handheld mapping GPS, they might end up at the last known position and no rocket. With no receiver at hand, unless the rocket is within eyeshot, life might get difficult. (Carrying around a laptop in the field is tedious and you can't read the screen readily in the sunlight.)

An alternative to an APRS H/T is, if one one owns an Android device/phone and any H/T, they can buy an $80.00 Mobilinkd TNC, https://www.mobilinkd.com/,
get APRSDROID and use an open source mapfile, https://aprsdroid.org/osm/ and be tracking APRS trackers for the cost of the TNC if they already have the other two compatible devices. Now they won't have the fancy "navigate to" features like that with a D72a and mapping GPS combo but they will be able to see the last rocket position on a map and walk toward it without too much trouble. Can pick up a new packet on the fly
since they can just rubber band the Mobilinkd to the H/T.

Another advantage is if one builds an EggFinder GPS tracker, they can use their Android device with "GPS rocket locator", https://play.google.com/store/apps/details?id=com.frankdev.rocketlocator after they do the simple grafting of a B/T board into the EF receiver.
One can have one receiving station for both devices. Kurt

Like Kevin and Mike I have the 8GR. It was the best HH investment I have made in a long time, especially as I timed my purchase as Yaesu was closing the model out!

I'm in the catagory of using a handheld GPS unit:




It takes about a minute to transfer the coordinates from the VX-8GR to the Garmin. From there, the Garmin is superior in every way as far as usability goes, it gets right down to giving me a distance of 10' and a bearing!

As much as I love our Garmin Montana, right now I would also look very, very hard at:

• Inexpensive Android tablet ($150 or so)
• The app "Backcountry Navigator"

All the best, James

Greg Young said:

Like Kevin and Mike I have the 8GR. It was the best HH investment I have made in a long time, especially as I timed my purchase as Yaesu was closing the model out!

Click to expand...

I just missed the 8GR and have an FT1D instead. Seems to be mostly the same, as long as you ignore the ridiculous digital modes. My only frustration is that it doesn't seem to update distance or bearing to target until it gets another APRS packet, which makes walking to the airframe a challenge when you're out of range.

Fdog said:

I'm in the catagory of using a handheld GPS unit:

It takes about a minute to transfer the coordinates from the VX-8GR to the Garmin. From there, the Garmin is superior in every way as far as usability goes, it gets right down to giving me a distance of 10' and a bearing!

As much as I love our Garmin Montana, right now I would also look very, very hard at:

• Inexpensive Android tablet ($150 or so)
• The app "Backcountry Navigator"

All the best, James

Click to expand...

James,

Are you manually keying the GPS coordinates, or do you use an interface cable? Perhaps I incorrectly assumed that the NEMA interface would automagically put the waypoint into the GPS.

Can you not just key the latitude and longitude into your smartphone and navigate to the rocket that way?

I am certainly not going into the woods without my phone anyway, so I would not be carrying anything extra. I loved my Garmin 60Csx before I got my first Droid. Now I use my Android smartphone for all mapping needs while hunting, fishing, driving, and even on multi-day backpacking trips.

Hopefully this won't fuel a raging debate... My understanding is that true GPS is indeed built into smartphones, such as the iPhone. However, without cell coverage you won't have maps, as they are stored on the server. Granted, for most people that is not an issue. In my case I'm planning for my first Black Rock launch, and need to be able to operate without cellular service.

Google Maps includes (or at least did) permit you to download satellite images for an area before leaving cell coverage.

But for outdoors stuff, I usually use BackCountry Navigator PRO which will allow download and storage of satellite and 24k ( "quad" ) topographic maps. Like I said, my phone is what I use for mapping on extended backpacking trips in the Smokies and other mountains that have no cell coverage at all. I use Samsung phones specifically so I can carry spare batteries and swap them out once a day or so.

For recovering a rocket, the map itself doesn't really matter, does it? Usually, you are on relatively flat land in woods or crops and just need a bearing toward the rocket, don't you?

MountainRocketeer said:

For recovering a rocket, the map itself doesn't really matter, does it? Usually, you are on relatively flat land in woods or crops and just need a bearing toward the rocket, don't you?

Click to expand...

I think so, which leads me back,to just using a single Kenwood or Yaesu radio with GPS.

Makes sense. I already have a $50 Baufeng, so I am trying to minimize added expense to get GPS capability.

Worsaer said:

I think so, which leads me back,to just using a single Kenwood or Yaesu radio with GPS.

Click to expand...

Easy enough to add a cable to a compatible APRS rig to do it automatically.

Compatible radios:

D7A, D7A(g) VX-8GR D72A

A few compatible Mapping GPS units:

Garmin 60Cs, 60CsX (OOP) Garmin 78 (still in production) All with the round port serial cable access and NMEA output
Etrex Legend A very basic unit that will give realtime navigation without a fancy map. Will get the job done.

Cable for the Legend: https://ep.yimg.com/ca/I/gilsson_2258_2848535 https://www.gpsgeek.com/products/in...-aprs-to-garmin-etrex-emap-geko-gps-receivers

Cable for the round serial port: https://www.gpsgeek.com/products/in...h-d7a-tm-d700a-aprs-to-garmin-4-pin-round-gps

Set the GPS for NMEA and 4800 and connect to the data socket to the radio. For the -8GR one has to go to the menu to make sure it outputs the
waypoint WPL NMEA words. The D7's and D72 have info in the instructions on how to attach the external mapping GPS. The Garmin GPS has to be set to NMEA in/output and not the proprietary "Garmin" data output.

Turn everything on and the rocket callsign will go into the waypoint directory of the mapping GPS. Can set the Garmin unit to "navigate to" and the unit will stay locked on the rocket. One can scroll to the map to see the position relative to the rocket and then to the compass rose datum line with distance information to the rocket or the last known position. Pick up a new packet and the rocket icon will "jump" to the new position. No manual input of data.

The cheapest is a used Legend. Takes awhile to get a GPS fix but is accurate once locked out in the open. Monochrome screen but is visible in sunlight.

Alot of folks who launch out in the boondocks don't feel a map is necessary. I'd tend to agree with them if there are no landmarks where they fly.
In that case, just two dots on a screen is all that's necessary to know which direction to go. The datum line, direction and distance to is icing on the cake with the connected mapping GPS units and is all automatic.

I'm a flatlander so I find it helpful if the rocket looks like it landed past this road or that road. Makes it easier to plan the trek out.

I did meet a flyer out at a launch who tried manually inputting the lat/long into his Garmin 60CsX GPS. Didn't read the manual carefully before coming out to the field so he was upset to say the least in trying to get the units to match. I showed how to interconnect his radio to his 60CsX and he is one happy camper with his Beeline GPS tracker now since he got the simple interconnect cable.

A caution about old D7 radios. I have two used D7's that work fine on 2 meters but the frequencies are out of spec on 70cm. Lucky if I get 1/2 block range with them and a Beeline GPS. Beware if considering purchasing an old D7. The D72 is way better. Kurt

MountainRocketeer said:

Makes sense. I already have a $50 Baufeng, so I am trying to minimize added expense to get GPS capability.

Click to expand...

Best option is the very portable Mobilinkd TNC I outlined above to attach to a non-APRS radio https://www.mobilinkd.com/ and an Android device that has a GPS in it. Use APRSDroid with Open Source maps and one will be able to walk towards their rocket's position while monitoring on the screen.

I will admit that one gets what they pay for. When I have my Kenwood TH-F6A connected to the Mobilinkd, it outperforms my Baofeng
UV-5R as far as a local digipeater being able to read the packets in a fringe situation. No matter what receive station one uses, try and do a ground
test and see what kind of range you get on the ground with your APRS tracking transmitter before you fly. Do it with the tracker mounted inside the rocket too for a better test. I don't think there is an iPhone app that will allow one to connect to a TNC and do APRS directly through an H/T like
the Mobilinkd. I believe Apple has a vise grip on the programming.
Kurt

I don't use GPS for the rockets, but if you don't mind typing the lat and long into the phone, GPS Essentials is a free app for the Android phone. If you have the phone already, free isn't a bad price. It works pretty well, will get you to within about 10 ft of the waypoint. Works very well for Geocaching.

I can't speak for others, but I know I'd find entering GPS coordinates into a phone on a hot launch day to be extremely frustrating. Especially if it's getting late, and I'm tired.

If I'm going to go to the level of GPS, I want it to just tell me where it is -- don't make me fumble-finger data into a device. Just do it for me.

-Kevin

Yes, GPS Essentials is very useful. In particular, it does a great job calibrating the electronic compass/GPS.

Worsaer said:

James,

Are you manually keying the GPS coordinates, or do you use an interface cable? Perhaps I incorrectly assumed that the NEMA interface would automagically put the waypoint into the GPS.

Click to expand...

There is a way to do this (with a NEMA cable that is); it is enough of a PITA that I've never bothered. It is alledgedly a pretty fragile (configuration-wise, not physically) setup, as well.

Hence I just transfer the numbers. It's only 12 key clicks or so.


All the best, James

ksaves2 said:

Best option is the very portable Mobilinkd TNC I outlined above to attach to a non-APRS radio https://www.mobilinkd.com/ and an Android device that has a GPS in it. Use APRSDroid with Open Source maps and one will be able to walk towards their rocket's position while monitoring on the screen.

Click to expand...

I wonder, how does this TNC compare to built-in modem (TNC) in APRSDroid / PocketPacket? They both rely on audio output from a radio, and how much better signal processing can you do on ATMega chip than in a smartphone app?

It's hard to justify $70 TNC vs $5 audio cable.

What is PocketPacket? I am not finding it in the Play Store.

PocketPacket is APRSDroid for iPhone

Nice thread Bill. It is timely and has enough expert input to allow for user choices.

troj said:

I can't speak for others, but I know I'd find entering GPS coordinates into a phone on a hot launch day to be extremely frustrating. Especially if it's getting late, and I'm tired.

If I'm going to go to the level of GPS, I want it to just tell me where it is -- don't make me fumble-finger data into a device. Just do it for me.

-Kevin

Click to expand...

Same here, this is why I use Telemetrum products and also the new Eggfinder with a BT adapter

At some point I'll post some observations. I purchased a used Garmin 60csx and a cable to go with my Kenwood TH-D7. Additionally, I couldn't resist a recent an eBay auction for a TH-D72. So now, I have both rigs to play with. I realize it's probably a matter of personal preference rather than which is truly 'better'.

I'm hoping to fly a new 54mm minimum diameter rocket on one of the new CTI L265 'Mellow' reloads at Balls in September, and REALLY want to find it after the flight. (Considering all the components, it's easily the most expensive bird that I will have ever flown.) I have a vested interest in finding which combination of equipment works best for me.

Any thoughts on the Garmin 320 "Astro"

Fdog said:

Hence I just transfer the numbers. It's only 12 key clicks or so.

Click to expand...

Yep. "Only". Except I don't wear my reading glasses at launches, I wear my sunglasses. And without my reading glasses, trying to transfer those numbers is an exercise in frustration. Add in a hot day, where I might be tired, and yeah....

No. I have a radio that has an integrated TNC so I don't have to play any of those games.

Or, I use a TeleMetrum and it shows me where the rocket is on a map.

-Kevin