Looks like a new GPS tracker on Missle Works site

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Anyway, what do you guys think about shrink wrapping the LiPo to the rocket board, ala BRB900? I see all these pics of Eggfinders and such with elaborate mounting of the battery and the board to a sled, creating a large footprint. My BRB900 is a nice, tidy package that fits almost anywhere with some bubble wrap.

As long as there is nothing to squish on the backside of the board, it should be doable
if you like. Kurt
 
Broke down and received a T3 yesterday. Did a quick setup and pairing with two Nexus 7's (2012 and 2013) and
"GPS Rocket Locator" works with it right out of the box. I paired the base via B/T to a Linux tablet without any
issue. Got placed at /dev/rfcomm1 (rfcomm0 had a Mobilnk TNC feeding a program on it). Changed the permission,
set the datastream coming in over the port as "My" local position and the strings were being decoded very nicely in Xastir.

I have a python script so I can get the strings converted to APRS and a tracked rocket can be displayed on the Xastir map nicely.

Tried to get Winblows to pair and use the HC-06 and as usual, it screws it up royally. Tried using the com10 and com13 ports to pipe the strings to a few apps and no freaking dice. This is a Winblows problem as opposed to
the T3. I did find with experimenting with the 3DR radios, the HC-05 seemed to work on a more stable fashion
than the HC-06. Go figure. Again, not a fault of the T3 but an issue with WinDoze.

Again, Android and Linux works fine. Could be my Winblows installation too. Kurt
 
Been playing with my T3 too. Nice piece of kit, but bigger (thicker) than I expected. I'm gonna get that thing in a 38 NC all nice and secure though...I'm getting close.
 
I am not smart enough to tell what is squishable, hence my question.

The X-bee module is on the other side and doesn't cover the full length of the board. Pulled out one of my LP Beeline GPS units and the T3 is physically smaller. If you go to shrink wrapping a 750mah 1S lipo on the backside, just make sure no metal touches the traces of the X-bee Rf module. Looks doable. Eyeballing it, it's about the same thickness as a Beeline GPS if you shrink wrap a 750Mah 1S pack to it . (There were no discrete components on the opposite side to get "squished" as far as I can see.)

I did a run and messed around for ~2 hours or a little bit more and nearly sucked a 500mah
1S pack dry. I apologize as I didn't keep track of time but I believe I easily got over 2 hours.

Remember, It's putting out 250Mw as opposed to 100Mw of other units. Power consumption is higher and should be expected. On this 33cm band, more power is desirable to stretch the range a bit. Kurt
 
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Glad to learn all your wares are operational, guys. Each system is end-to-end tested after I setup the XBee network configuration and make the radio power junction shunt. End-to-end is from Rocket uBlox7/XBee to Base XBee/HC-06 to Android...

These are power hungry little beasites with all that NMEA "payload fluff" and the ~200ma pull during transmit... my bench test was just minutes shy of 4 hours continuous data using a 1S 750mAh NanoTech.

We'll be caught up this weekend on backorders and I'm hoping to design some PLA boxes and adapters for easy setups.
 
Something I would like to see in the design of the box is someway to either hang it around your neck or a belt/pocket clip.
 
It was hard (at least for me) to get this thing in a 38 NC, but I got it last night...that terminal block was brutal, but convenient to have. Again, Jim, nice product.
 
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I got the T3 system a couple weeks ago and got some 600mhA S1 batteries in and charged last night. I fired up the transmitter and reciever, synced to my cell phone and installed Rocket Locator. The better half walked the transmitter around the neighborhood and everything went great.

Used it three times at BattlePark today. Highest flight was +5700 ft., the fastest was ~650 mph, the farthest landing was about 2000 ft away. The transmitter and battery was wrapped in bubble wrap and then sandwiched between two pieces of foam rubber and wrapped with electrical tape. That was taped to the shock cord. The receiver was mounted in a small plastic box by drilling a 1/4" hole in it and tightening the nut and washer on the antenna mount. A switch was added and the lipo was taped into the box.

Everything synced up just fine and Rocket Locator app worked OK. It took a while to get the maps to show up and was probably a function of cell service, although we get 2 or 3 bars of 4G at the field. It started with just the map, but later showed the Satellite view which works very well. I did find that once you have the landing position of the rocket, you can turn off the receiver and Rocket Locator will still show the rocket location and yours and direct you to the rocket. The only thing about going out and retrieving without the receiver is that the position might not be quite so accurate. Without updates from the transmitter as you get closer and the GPS has settled in, you might be off a bit. I was 75 to 100 ft off on one flight. The ones where I took the receiver along were much closer.

All in all, a great little system and everyone that saw it and how it works on the phone wants one too.
 
Nice report, Handeman.

I was reading through the documentation and found this odd warning:

IMPORTANT: Ensure your T3 is oriented in your rocket or av‐bay to avoid having the patch antenna placed
near or against your launch pad rail or tower rails.**This proximity will block all satellite reception and
prevent acquisition of a GPS coordinate fix.


This is the first time I ever saw a tracker warn about a launch pad blocking reception! How much is "near?" I mean, my 38MD is going to have the antenna 19mm away from the rail, and there is not much I can do about that.

Did anybody experience this, and did reception return after the rocket left the pad?
 
wireless isn't my wheelhouse, but I can imagine it meaning "Don't stick the tracker so the rail is sitting smack in front of the antenna"

Awaiting clarification
 
I don't know if I've had that issue or not. I don't think so. I know the older one has had issues with the rail causing it to loose lock with the handheld unit. I've witnessed a few scrubbed launches because of that. I usually watch the track of the rocket from the table to the RSO and then to the pads. If it looses lock then, I don't know. The Rocket Locator app continues to show the rocket location if it has a lock or not. Once it's launched, it has worked great.
I haven't had any problems with it and was sure glad I put it in my L3 bird today. I wasn't going to because it's so big and only going about 5500 ft. I wasn't going to loose sight of it. But after the first rocket went off the away pad and I saw how strong and direction of the upper level winds, I put it in. Ended up 3/4 mile away and in a 40 acre corn field. The Rocket Locator had downloaded the satellite images so I had a good visual of nearby landmarks. Ended up walking right to it. We brought the receiver along this time and it was only off be less then 5 ft. by the time we got to the rocket.
 
I was reading through the documentation and found this odd warning:

IMPORTANT: Ensure your T3 is oriented in your rocket or av‐bay to avoid having the patch antenna placed
near or against your launch pad rail or tower rails.**This proximity will block all satellite reception and
prevent acquisition of a GPS coordinate fix.


This is the first time I ever saw a tracker warn about a launch pad blocking reception! How much is "near?" I mean, my 38MD is going to have the antenna 19mm away from the rail, and there is not much I can do about that.

Did anybody experience this, and did reception return after the rocket left the pad?

Sorry for the confusion...

The GPS patch antenna is very directional, so if it's pointing at the rail while situated in your cone or av-bay you're gonna block the majority of its horizon/satellite view. It's not the proximity of the rail and the patch antenna, it's the orientation of the patch antenna in relation to the rail.

Hope that clarifies what I was meaning to say...
 
Perfectly clear.

If you want to light the room with a flood light, don't shine it strat at a column lol
 
I had just bubble wrapped it and taped it to the shock cord. Guess I got lucky, but will be more conscience of the orientation from now on. All I know is, it probably saved me hours of wandering through 8 ft. high corn yesterday.
 
I had just bubble wrapped it and taped it to the shock cord. Guess I got lucky, but will be more conscience of the orientation from now on. All I know is, it probably saved me hours of wandering through 8 ft. high corn yesterday.

That works and is quite common... pay attention to the patch orientation relative to your rail guides and all will work well. The alternative is to mount the transmitter horizontally so the patch points skyward, but that requires a much larger diameter airframe.
 
I don't know if I've had that issue or not. I don't think so. I know the older one has had issues with the rail causing it to loose lock with the handheld unit. I've witnessed a few scrubbed launches because of that. I usually watch the track of the rocket from the table to the RSO and then to the pads. If it looses lock then, I don't know. The Rocket Locator app continues to show the rocket location if it has a lock or not. Once it's launched, it has worked great.
I haven't had any problems with it and was sure glad I put it in my L3 bird today. I wasn't going to because it's so big and only going about 5500 ft. I wasn't going to loose sight of it. But after the first rocket went off the away pad and I saw how strong and direction of the upper level winds, I put it in. Ended up 3/4 mile away and in a 40 acre corn field. The Rocket Locator had downloaded the satellite images so I had a good visual of nearby landmarks. Ended up walking right to it. We brought the receiver along this time and it was only off be less then 5 ft. by the time we got to the rocket.

Be careful!! Recovery using a photomap can get pretty addictive and leads to one flying more rockets in a given timeframe. Kurt
 
That works and is quite common... pay attention to the patch orientation relative to your rail guides and all will work well. The alternative is to mount the transmitter horizontally so the patch points skyward, but that requires a much larger diameter airframe.

OK, the words are getting more confusing. To me, the logical orientation is to position the antenna parallel to the long axis of the transmitter and parallel to the rail. Is this picture correct?

Capture4.PNG
 
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