# Looks like a new GPS tracker on Missle Works site

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#### farsidius

##### semper discens
I just mentioned this on another thread in The Watering Hole, but I was on Missile Works web site the other day and noticed he has a listing for a new GPS tracker called the T3 System. Has anyone else seen this or talked to Jim about it? According to the description it's based on the open source project that Derek posted here a few years back (I built a couple of these): https://www.rocketryforum.com/showthread.php?53120-Rocket-Track-Open-Source-GPS-Tracker-for-Smartphones, and uses the core components of his RTx system. You'll need a Bluetooth enabled device to track, but looks like a good, affordable option. Not available yet - hopefully soon?

Here's the blurb from the webpage:

The T3 Tracker System (Tiny Telematics Tracker) is a simplified and scaled down version of our RTx/GPS system. Even though the T3 system is our lower cost "Buy and Fly" tracker system, it still uses the same proven core components as its big brother RTx, specifically:

- uBlox7 GPS Engine
- 1/4 watt XBee Radio Modems
- HC-06 Bluetooth Module

The T3 system relies on your Bluetooth ready Android device and uses any NMEA/Bluetooth stream reading Android app (Blue GPS / Rocket Track / Rocket Locator) which are all available in the Google Play Store. The T3 system is based upon the original "Rocket Track" open hardware project.

Your XBee radios come pre-configured for private networking operation as we manage all radio network ID's just like we do for our RTx systems.

Forgot to add a link to the webpage for those interested: https://www.missileworks.com/store/#!/T3-GPS-Telematics-Tracking-System/p/90226446/category=19848147

-brant

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#### MWC

##### Well-Known Member
Glad to know some are paying attention to the shopping cart!
I'm hoping these are ready for delivery in the next few weeks... easy "buy and fly" with all up privately networked 250mW 900Mhz ISM XBee's.

I'm looking at a firmware tweak for the RTx System that would allow a dual-boot or a config change to display the pertinent NMEA data from a T3 transmitter. This will allow a single "base" handheld and provide mix and match capability (RTx or T3 rocket transmitter). This tweak can also potentially support the autonomous navigation provided by the "Navigator" version.

I'll have more to report soon.

#### ksaves2

That's a nice choice to get 250mW out of a smaller package that works with mapping software. I see likely Santa will be busy this year. Kurt

#### 0011001100

##### A Person
Jim, any idea on cost? Already planning on buying an RRC3 for deployment and this would go perfect with it once I fly some larger motors in this bird.

#### jeff2space

##### Well-Known Member
Jim, any idea on cost? Already planning on buying an RRC3 for deployment and this would go perfect with it once I fly some larger motors in this bird.

#### MikeyDSlagle

##### Well-Known Member
Awesome! 150 bucks for a GPS tracker! Where do I sign up?

This would round out me being Missileworks standardized in all my rockets. Well, until I need a timer. Maybe a smaller cheaper timer than the PET2+ is on the horizon? That would urge me to go Missileworks all the way.. well except for the occasional small rocket needing a Quark.

#### Nytrunner

##### Pop lugs, not drugs
TRF Supporter
I'm intrigued as well! Is Ham licensing required for this system? The system I've been looking at for L2 is more expensive and requires Ham, so I've been browsing around for alternatives.

Also, does it require cell signal for the Android receiver (ie. My phone) to function properly?

#### Exactimator

##### Well-Known Member
Are there recommended batteries for each component?

#### ksaves2

I'm intrigued as well! Is Ham licensing required for this system? The system I've been looking at for L2 is more expensive and requires Ham, so I've been browsing around for alternatives.

Also, does it require cell signal for the Android receiver (ie. My phone) to function properly?
No since it's on the same ISM band as the Rtx, Ham licensing isn't required there. The terminal application you use would be your responsibility, I would suggest you wait until Jim releases the instructions as far as asking questions on the need for cell phone
service. Does it need the cell phone service to track? No. Do you need the cell phone service to have access to maps? Maybe. You can download maps in advance with the app "GPS Rocket Locator" and cache them on your device for use in the field.
If you have cell phone/data access, the app will automatically pull up the maps you need if you want to use the maps "live". But for the tracker to work, you don't need internet or cell phone access onsite whatsoever. It's nice if you are missing
a map tile or two, to download 'em live. A Nexus 7 2013 flo that is WiFi only I've used fine out in the field. I downloaded maps to save via Wifi

GPS Rocket Locator will work without maps and a blank screen. Trust me, that's boring but doable. Also it's reassuring if you don't have a maptile for the zoomlevel you want to use, you still get a datum line from your position to the last known position of your rocket. I've seen some APRS tracking programs simply will not work if there are no maps to be had for a device.

When pairing B/T ground stations, get the heck away from other people who are doing the same thing because your tablet or phone can get "confused". I learned this when I wanted to have two receive stations monitoring an EggFinder.
The paradigm is the same. Tracker sends position via Rf to the Receiver. Receiver sends the signal stream via B/T to your tablet or phone. The Rf encoding I believe is different between the EF the the T3 so don't asked the question
are they compatible? I believe the answer there is no.

Another bit of advice, a 7" tablet is "nicer" to look at than a small phone screen. No matter what you use, you might want to get a modestly deep cardboard box, paint the inside with flat black paint to set your tablet or device in to shield against
the sun's glare. Your screen will be unreadable in the direct sun. Kurt

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#### farsidius

##### semper discens
The \$149 is a complete system price... I'll break out a separate/extra transmitter offering soon and post it up in the shopping cart. It's my goal to wedge in the NMEA parsing operation for use with an RTx base.
Having the capability to use this with my RTx base would be awesome. I hope the NMEA parsing config change will work out. I can think of a few of my smaller birds where I could use this smaller T3 transmitter.

Keep up the good work.

#### Nytrunner

##### Pop lugs, not drugs
TRF Supporter
No since it's on the same ISM band as the Rtx, Ham licensing isn't required there. The terminal application you use would be your responsibility, I would suggest you wait until Jim releases the instructions as far as asking questions on the need for cell phone
service. Does it need the cell phone service to track? No. Do you need the cell phone service to have access to maps? Maybe. You can download maps in advance with the app "GPS Rocket Locator" and cache them on your device for use in the field.
If you have cell phone/data access, the app will automatically pull up the maps you need if you want to use the maps "live". But for the tracker to work, you don't need internet or cell phone access onsite whatsoever. It's nice if you are missing
a map tile or two, to download 'em live. A Nexus 7 2013 flo that is WiFi only I've used fine out in the field. I downloaded maps to save via Wifi

GPS Rocket Locator will work without maps and a blank screen. Trust me, that's boring but doable. Also it's reassuring if you don't have a maptile for the zoomlevel you want to use, you still get a datum line from your position to the last known position of your rocket. I've seen some APRS tracking programs simply will not work if there are no maps to be had for a device.

When pairing B/T ground stations, get the heck away from other people who are doing the same thing because your tablet or phone can get "confused". I learned this when I wanted to have two receive stations monitoring an EggFinder.
The paradigm is the same. Tracker sends position via Rf to the Receiver. Receiver sends the signal stream via B/T to your tablet or phone. The Rf encoding I believe is different between the EF the the T3 so don't asked the question
are they compatible? I believe the answer there is no.

Another bit of advice, a 7" tablet is "nicer" to look at than a small phone screen. No matter what you use, you might want to get a modestly deep cardboard box, paint the inside with flat black paint to set your tablet or device in to shield against
the sun's glare. Your screen will be unreadable in the direct sun. Kurt
Thanks K, that gives me some lines of thought to start down. This may be exactly what I'm looking for to start out before investing in the higher end ones (without having to find someone to solder some Eggfinder for me).

#### MWC

##### Well-Known Member
Are there recommended batteries for each component?
1S or 2S Lipo will work fine... pick a mAh capacity based on your preference.
I'll do some battery characterization as part of my documentation efforts.

#### MWC

##### Well-Known Member
Having the capability to use this with my RTx base would be awesome. I hope the NMEA parsing config change will work out. I can think of a few of my smaller birds where I could use this smaller T3 transmitter.

Keep up the good work.
Thanks, Brant.

My goal at the onset of the RTx project was to make a universal board that could operate in either role as "base" or "rocket" device. That goal got hijacked unfortunately. We learned that the networking latency of the XBee radio when configured in a multicast mode interfered with data packet multiplexing when the RTx is tethered up with the RRC3. The net result here is while the electronics and the firmware are all the same, the radio configurations are different.

With this difference as a matter of fact, I can actually look at code segregating since each board is uniquely configured anyway... that's my backdoor (separating the rocket and base board firmware into separate projects). The NMEA parser will allow RTx base display and T3's to comingle and will operate as a "Standard" unit (display only) or "Navigator" (directing you to the landing waypoint autonomously).

#### farsidius

##### semper discens
Are there recommended batteries for each component?
I use these with my Missile Works GPS trackers.

https://hobbyking.com/en_us/turnigy-nano-tech-750mah-1s-35-70c-lipo-pack-walkera-v120d02s-qr-infra-x-qr-w100s.html

I use one of these (3 to 4 flights) in the base unit and change it out at the end of the day. I change them out in the transmitter after two flights -mostly because I'm paranoid about a flight going south that will take me hours to find. I recall Crazy Jim saying that he got about 10 hours from a 1S batteries on the RTx transmitter when he was testing it last year. I, personally, have not tested these out to depletion.

-brant

#### farsidius

##### semper discens
Thanks, Brant.

My goal at the onset of the RTx project was to make a universal board that could operate in either role as "base" or "rocket" device. That goal got hijacked unfortunately. We learned that the networking latency of the XBee radio when configured in a multicast mode interfered with data packet multiplexing when the RTx is tethered up with the RRC3. The net result here is while the electronics and the firmware are all the same, the radio configurations are different.

With this difference as a matter of fact, I can actually look at code segregating since each board is uniquely configured anyway... that's my backdoor (separating the rocket and base board firmware into separate projects). The NMEA parser will allow RTx base display and T3's to comingle and will operate as a "Standard" unit (display only) or "Navigator" (directing you to the landing waypoint autonomously).
Thanks for the explanation Jim. If these become available by October, I may pick one up to play with at our October launch.

#### MWC

##### Well-Known Member
I recall Crazy Jim saying that he got about 10 hours from a 1S batteries on the RTx transmitter when he was testing it last year. I, personally, have not tested these out to depletion.
-brant
Correct for RTx... 10 hrs with 1S 750mah Lipo.
I don't expect the T3 to be as efficient and it's blindly pumping all the uBlox7 default NMEA sentencing (4 or 5 by default), so more transmitter time.

#### Crazyrocket

##### Well-Known Member
Jim, will the T3 record flight data like your RTx version? Sounds like another great product. Cannot wait for it to come out, especially if it works with an existing base unit.

#### ksaves2

Jim, will the T3 record flight data like your RTx version? Sounds like another great product. Cannot wait for it to come out, especially if it works with an existing base unit.
I bet the answer here is judging by the hardware size. I think the feature list would have mentioned an onboard logger which is actually the ideal way to log a flight. Positions get missed due the vagaries of Rf propagation during the high dynamics of a rocket flight. Things settle down when under the slower descent of the main parachute. Find the tracker and download all the positions seen by the GPS.

That said, your terminal application that you use will likely allow you to record the stream to a file where you can access it and manipulate it however you want. In that case, you would be on your own and would have to learn how to do it from whatever application you are using.

I suggest if you want to automatically navigate to your rocket or "last known position", get use to and become familiar with the Android app "GPS Rocket Locator".
It will keep track of your local position and the rocket position. The Android app "B/T GPS: https://play.google.com/store/apps/details?id=googoo.android.btgps&hl=en Will allow you to use the data stream from your T3 receiver instead of your local GPS and it will display the rocket position on a map. It will not show where you are nor how to navigate to the rocket. You could copy the lat/long from this app into another device to navigate to the rocket
but that entails more work and input one wrong number and you're off on a wild goose chase. Also, I recall one needs a live internet connection to download the
maptiles or it won't work. Something to know for WiFi only devices. B/T GPS is good for local ground testing and seeing how many satellites are being used by

You got an Android phone with a backside camera? This app is pretty cool to get a snapshot of the satellites that are overhead at your position. Input your local
lat/long and point the camera overhead. Pretty nifty, fast and easy to use once you get the hang of it: https://play.google.com/store/apps/details?id=com.nec.android.qzss.gnssview

Kurt

#### MWC

##### Well-Known Member
Jim, will the T3 record flight data like your RTx version? Sounds like another great product. Cannot wait for it to come out, especially if it works with an existing base unit.
It does not record... I'm looking at integrating an "easy" connection for an "open-logger" board if recording is desired. Note that this style of recording would not be acceptable for TRA records.

#### Crazyrocket

##### Well-Known Member
Thanks Jim. That's what I figured. Since I have the navigation system this is a great addition for small fliers.

Kurt, thanks for the information. Looks like there are a couple of different options if I want to record the data. Primary use will obviously be to find my rocket. Data is always nice to have but not necessary.

#### MWC

##### Well-Known Member
I made the production tweaks to the PCB layout today and I'll be ordering boards after the holiday weekend. Adding an open logger board will be straightforward and I'm planning on offering a connection via a 0.1" header cable. It can connect to the HC-06 pads as these are vacant for a rocket board.

It does not record... I'm looking at integrating an "easy" connection for an "open-logger" board if recording is desired. Note that this style of recording would not be acceptable for TRA records.
Looking at the rules it's not obvious to me why that would not be approved for use in records. They want to see data that was recorded on-board rather than downlinked, but I didn't see anything about merging 2 products to generate in=flight recordings.

#### ksaves2

Looking at the rules it's not obvious to me why that would not be approved for use in records. They want to see data that was recorded on-board rather than downlinked, but I didn't see anything about merging 2 products to generate in=flight recordings.
Some GPS chipsets are supposedly more "accurate" with altitude recording than others. SirfIV = "BAD" Ublox = "BETTER" along with a few others. High altitude balloon guys will swear a SirfIV can do just as
good at altitude but a lazy balloon flight does doesn't compare to rocket dynamics.

The other thing with record hunting I believe there is a protocol to follow so data can't be fabricated or altered. With the "approved" devices there has to be someone of authority there to attest this is a valid attempt and the data
is good.

Use the right chipset, and actually use a plug-in memory board/card and I don't see what would be wrong there. It might be easier than giving the "whole" device to the governing authority. It would entail that the device maker would
have to "petition" a BOD for inclusion on a list of acceptable devices. I think it would be easier to witness the card being inserted/loaded on to a tracker and be there when recovered to accept the card when the ebay is opened
at the landing site.

Shoot, I think Greg Clark didn't "do anything" except design a robust APRS system and the TRABOD sent him a note his Beeline GPS was acceptable for high altitude attempts. As I recall, I think he didn't petition for its inclusion but
was notified it was accepted out of the blue. Kurt

#### MWC

##### Well-Known Member
It is my understanding the TRA records committee desires the proprietary/persisted GPS data files to be "secured" rather than human readable/modifiable as would be the case with straight ASCII/NMEA sentencing... now albeit it would be a pain to tweak NMEA sentencing (including creating a valid checksum post tweak), but that's the precedent as I am aware of it. If there are "records committee members" herein that peruse these threads, they could speak first hand to this.

#### Nytrunner

##### Pop lugs, not drugs
TRF Supporter
Well there goes the rest of next month's rocket budget......
How long will the shipping credit be open?