Trackers: T3 vs Featherweight vs ??

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Vombatidae

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I need a GPS tracker for a planned August launch. It won't really be going that high or (hopefully) drifting that far, but I want some experience with it before I put it in something more extreme.

Requirements are:
- 900MHz (no mobile service to speak of at the launch site)
- Communicates with my Android phone
- Doesn't require me to solder SMDs
- Reasonably priced (i.e. two trackers + ground station < $500)
- Available no later than mid June, so I can integrate into the av bay and ground test
- Fits in 54mm coupler

Preferences include:
- Fits in 38mm coupler
- Handles two or more trackers per ground station
- Capable of handling longer ranges/altitudes in case I go somewhere with higher waivers.

All things being equal, I would order the Featherweight for the announced features and because I've been very happy with my Raven 3. However, my hopes of having it in hand and talking to my Android in time are dwindling. The BRB900, Eggfinder, TeleGPS, and others I've seen don't meet my requirements as far as I can tell, but I'm open to suggestions.

Thoughts?
 
Why are you limiting to 900 MHz?
Yea I wouldn't hold my breath for the Featherweight as they haven't even released an iOS system yet.
I have the Missile Works RTx Navigator system which requires no smart phone and will walk you right up to your rocket and they have a blue tooth module you can pair with an Android. I love it. Cost is about $320 once you add some accessories.

https://www.missileworks.com/store/...Navigator-System/p/67781466/category=25228107
 
Why are you limiting to 900 MHz?

Even though it isn't a huge hassle, I'm just not interested in a Technician's license for 435 or 145 MHz, and 900 MHz seems to be more than adequate. If there are other options I'm not aware of, I would love to hear about them.

If I had a MissleWorks RRC3, the RTx/GPS would be an easy choice, but since I don't, their T3 seems like it would do just as well.
 
You can get an Eggfinder with the LCD display for 1/4 of your budget, and there are people that assemble them for a small fee... see mctronics.webs.com With all the options and completely assembled, its' probably going to come in way way under your budget... leaving you more money for motors. :)

Lab Rat Rocketry makes some nice 38mm NC mounts for them too... https://www.labratrocketry.com/
 
You don't need the RRC3 to use the RTx system. It operates independent of the altimeter. Connecting to the RRC3 is just an option.

I have the RTx system with one base unit and 4 rockets units. Just let Jim know you want to add a rocket unit to an existing base unit when you expand.

I tether to the RRC3 in some rockets and not in others. Works great both ways.
 
The Eggfinder mini and Missileworks TRS have the advantage of being available now. I believe that Featherweight has said that when it is available it will be iOS only for a time. I have both the EF mini and MWT3 and have pushed my EF mini over 18 k with no issues.
 
I like my TeleGPS but wanted another system - this one completely turnkey. I got the Eggfinder and the LCD receiver but realized pretty quickly that it's way beyond my current ability to put them together. I paid Connor McGrath (search here on the forum to find him) to assemble them for me and he did a fantastic job at a reasonable price. I made a few other "upgrades" to my setup and the result is a fantastic tracker solution that cost me in total a few pennies over $215. You simply can't beat it.

Here is the complete breakdown for an elegant, fully turnkey system. you'll need to scale up your price accordingly for two tranmitters

Eggfinder TX - $50 (Black Friday price)
Eggfinder LCD RX - $50 (Black Friday price)
SMA Connector x2 (from Eggtimer) - $6
Linx 1/4 wave stick antenna for TX (Ebay) - $6.75
1/2 wave stick antenna for RX (from Eggtimer) - $10
Blackaero LCD enclosure - $20
Assembly Service for RX and TX (this included adding the SMA connectors to the transmitter and receiver as well as the power switch and momentary button that came with the LCD enclosure, and return shipping) $52.50
1500 mah lipo for LCD RX (Hobbyking) $10
300 mah lip for TX (Hobbyking) $5
Bluetooth module (Ebay) $6

I forgot to ask that JST connectors be soldered on to the transmitter and receiver to connect the batteries, so I did those myself, but you could have them put on when it's assembled. The jst pigtails cost about a buck each and you can get them when you buy your batteries. The Bluetooth module simply plugs in and in theory allows you to pair with an android device. I haven't been able to get mine to work (it pairs but doesn't send data) but I think I got a bum unit and it's being replaced.

This may seem like a lot of hassle, but really it's just ordering stuff and waiting for it all to come in, then sending the necessary parts to be assembled, more waiting then a little bit of work on your end to get everything configured and up and running. I was glad to save the money, but it also ended up being a perfect solution for what I needed - and it looks good too.

I also got one of Chris Bender's custom nose cone sleds and it's made for 38mm, but he's now got a 54mm bulkhead that it works brilliantly with.
 
You mentioned Missileworks T3 in your title. That is your answer. $150 for a complete system, $80 for additional TX. You need to add batteries and an enclosure. This product eliminates the hassle of sourcing parts and building an Eggfinder for essentially the same or less cost.

You have 3 Android app choices for pairing to your T3, and they all have some quirks. They are all nearly impossible for me to read on a bright sunny day. This is where a dedicated LCD receiver works better, like, say, BRB900.
 
You mentioned Missileworks T3 in your title. That is your answer. $150 for a complete system, $80 for additional TX. You need to add batteries and an enclosure. This product eliminates the hassle of sourcing parts and building an Eggfinder for essentially the same or less cost.

That is what I was thinking, but wanted check here to see if I was missing anything.
 
This product eliminates the hassle of sourcing parts and building an Eggfinder for essentially the same or less cost.

I stand corrected :) I probably would have gone with this system myself but at the time I didn't have a Android device, so a stand-alone LCD receiver for me was my only option.
 
If you're talking apples & apples, an Eggfinder Starter Set with a transmitter and a Bluetooth-interfaced receiver (not the more expensive LCD receiver) is $90. If you want a handheld case with all the hardware, it's $8... all from one source.

If you're looking for a LCD display, the Eggfinder LCD Starter Set is $120, and that includes the case and hardware along with the transmitter and receiver. Yes, you have to build it, or get somebody else to build it, but it's half the cost of any other display solution out there. You can always add the Bluetooth module to the LCD receiver... I know a lot of people that do just that, and use their Android device as the primary display. Sometimes Bluetooth connections drop... if that happens, you have the coordinates on the LCD display to back you up.
 
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BRB900 Complete. GPS coords transmitted to LCD receiver. You also need a navigator to walk you out to the rocket. I use an old Magellan 315, purchased on eBay for $20.
 
I fly a standard Eggfinder and love it. In hindsight I kinda wish I'd got the Mini- it'd be a lot easier to fit in small spaces.

I haven't had 100% success with mine, but all the issues have been phone-caused rather than gadget-caused.

I got it on sale with the case and Bluetooth for $75... Can't go wrong there!
 
TeleGPS by Altus Metrum got our project rocket back. Worked through tree lines and over hills. That HAM exam felt harder than some mechanical engineer exams. Basically I memorize bullsh*t. There were questions not on study guide. Guess. That AIM extra will work to 105 G's. The FCC ones get you all your data real time and sometimes though the boost phase. One team tried an Eggfinder this year and it lost all data during boost. Bout 60.6 G's I know a tele takes the Eggfinder can't.
 
Even though it isn't a huge hassle, I'm just not interested in a Technician's license for 435 or 145 MHz, and 900 MHz seems to be more than adequate. If there are other options I'm not aware of, I would love to hear about them.

If I had a MissleWorks RRC3, the RTx/GPS would be an easy choice, but since I don't, their T3 seems like it would do just as well.
Try it man. You don't know what your missing. It's fifteen bucks to test. It's valid for ten years. Once you have it there's much more data you have. You can select baud rates for better range. You can power the yagi for better range. The quality of signal is simply better. I passed it first try and failed two practice exams. You got this.
 
Try it man. You don't know what your missing. It's fifteen bucks to test. It's valid for ten years. Once you have it there's much more data you have. You can select baud rates for better range. You can power the yagi for better range. The quality of signal is simply better. I passed it first try and failed two practice exams. You got this.

Perhaps your nicest post to date. "You got this" now.
 
Bat-mite - why did you recommended the BRB900? After following the link you provided and reading the documentation, it seems to cost 2x the T3 for very similar performance, although the LCD display is available. I've read many of your posts... you've been at this a while and know your stuff. Is there something I'm missing? Thank you!
 
I have the Missile Works RTx Navigator system which requires no smart phone and will walk you right up to your rocket and they have a blue tooth module you can pair with an Android. I love it. Cost is about $320 once you add some accessories.

https://www.missileworks.com/store/...Navigator-System/p/67781466/category=25228107

I like the RTx navigator system also. I also have a BRB900 and the T3.

The RTx is the easiest. No need to mess with a phone or laptop. With the navigator system it will tell you how far away the rocket is from your current position and give you the direction to walk. It also gives an estimated time to target once you start moving.

If you want to have a satellite map to look at and don't mind pairing with a phone, get a T3.

BRB900 is the same as the T3 except you need to manually enter the coordinates on a mapping app. Less user friendly than the T3 and it costs more. I would not buy a BRB900 today.
 
Bat-mite - why did you recommended the BRB900? After following the link you provided and reading the documentation, it seems to cost 2x the T3 for very similar performance, although the LCD display is available. I've read many of your posts... you've been at this a while and know your stuff. Is there something I'm missing? Thank you!

I have both. The BRB900 was the first widely-available system using license-free 900 MHz. I was an early adopter in 2010. It is long in the tooth and needs to get refreshed to warrant the price. However, it comes with batteries, charger, switches, LCD receiver, enclosure, volatile memory, and programming software. It works right out of the box. I recovered a rocket 2+ miles away across Indiana farmland with it.

The T3 requires you to supply all the above stuff and fuss with your phone. I've had the T3 for 6 months, and I am still not confident with it. The main problem for me are the shitty free Android apps you need to pair with the receiver to read the GPS data. RockeLocator, RocketTrack, GPSBlue all have their quirks. All are nearly impossible to read in bright sunlight with their small fonts.

I used RL and GPSB with the T3 in back to back flights this weekend, with the display just scrolling the log file of NMEA strings, because the mapping functions are flakey. I hoped to pause the log file and punch the coordinates into my trusty Garmin. However, when I turned my phone from portrait to landscape orientation, the log data disappeared and reset! Coincidence? I don't know, but WTF? Luckily, I had visual sight of my landings.
 
I like the RTx navigator system also. I also have a BRB900 and the T3.

The RTx is the easiest. No need to mess with a phone or laptop. With the navigator system it will tell you how far away the rocket is from your current position and give you the direction to walk. It also gives an estimated time to target once you start moving.

If you want to have a satellite map to look at and don't mind pairing with a phone, get a T3.

BRB900 is the same as the T3 except you need to manually enter the coordinates on a mapping app. Less user friendly than the T3 and it costs more. I would not buy a BRB900 today.

Used the T3 to track the sustainer for a two-stage project that landed over two miles away with zero issues. First real test for it.
 
I used RL and GPSB with the T3 in back to back flights this weekend, with the display just scrolling the log file of NMEA strings, because the mapping functions are flakey. I hoped to pause the log file and punch the coordinates into my trusty Garmin. However, when I turned my phone from portrait to landscape orientation, the log data disappeared and reset! Coincidence? I don't know, but WTF? Luckily, I had visual sight of my landings.

I've seen other people with similar RL issues. That's why I recommend using the LCD receiver with the Bluetooth module... if you lose the Bluetooth feed or the software craps out, you still have the coordinates as a backup.
 
I've seen other people with similar RL issues. That's why I recommend using the LCD receiver with the Bluetooth module... if you lose the Bluetooth feed or the software craps out, you still have the coordinates as a backup.

Cris can you suggest another mapping app besides RL that would work with this exact setup? I have the LCD w/bluetooth and looking forward to using it for the first time at LDRS. Can't get RL to work and according to posts here the app is broken. I'm fine with punching in coordinates into my iphone, but I like the idea of it going directly to my android tablet.
 
I've seen other people with similar RL issues. That's why I recommend using the LCD receiver with the Bluetooth module... if you lose the Bluetooth feed or the software craps out, you still have the coordinates as a backup.

Agreed. LCD receiver is rock solid. With the Android apps, it is a gamble. I guess I will take frequent screen captures of the app during flight in case the software or Bluetooth fails. I'll even pay for a more reliable Android app! Is there anything else out there?
 
Ahhhh folks, I ranted tor years about screen glare after trying to read a laptop screen in sunlight in '07.
Get a cardboard box 6 inches deep or so and paint the inside with flat black paint. Also, get a matte screen protector and not some shiney clear one if you don't want to be looking at your own reflection. Stick the device in the box and face the sun. I like 7 inch or larger tablets and Nexus 7 2013's are ideal. Easier to see. If still having glare, in a pinch put a jacket or blanket over your head to cut the glare. Oh with cardboard you can cut a thumb hole and hold it in one hand.
With Eggfinders practice outside if using a mapping program. Be certain both devices have a good GPS lock before pairing via B/T. Try and be clear of anyone else using Eggfinders because B/T issues can arise. It's easy to walk out a ways to get the devices paired. Just get out of B/T range of other eggfinders to do the pairing. Once locked you're good to go. Kurt
 
Agreed. LCD receiver is rock solid. With the Android apps, it is a gamble. I guess I will take frequent screen captures of the app during flight in case the software or Bluetooth fails. I'll even pay for a more reliable Android app! Is there anything else out there?

Suggestion: Eggfinder App? We would pay $$$ for this. (at least I would)
 
Suggestion: Eggfinder App? We would pay $$$ for this.

There's a hidden problem with apps and Google. I forget which one, but one of the tracker apps had Google map support and dropped it. The LocalWx program I posted elsewhere to find the NWS point forecast for a location uses a Google API.

Here's how Google gets ya. The Geo API that LocalWx uses is licensed to me as a developer. Up to a certain number of accesses per month, there is no charge for using the API. When the access count goes above that, Google charges the developer. Chances are good this is why map support was dropped from the other app. A new app would need to either (a) be priced to handle the Google map charges it is sure to incur, or (b) use Open Street Map or another similar source.

And then there is the darn visibility problem. As ksaves2 says, LED screens are almost useless in the sun. I was in Idaho for the eclipse trying to get sharp focus with a Nikon D300 using sunspots as a reference. I couldn't even see the image without a jacket over my head.

So I'm thinking maybe what we need is an LCD gizmo that uses Bluetooth or wires to get the data from the Rx and display it in a way we can use it in the sun. When I think of the huge programming difference between iStuff and droids, this is almost simpler than writing two apps in completely different programming languages.

Edit: I'm not thinking of a 16x3 alphanumeric display or such, but a LCD dot matrix that has a low res pointer along with alphanumeric data.
 
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Agreed. LCD receiver is rock solid. With the Android apps, it is a gamble. I guess I will take frequent screen captures of the app during flight in case the software or Bluetooth fails. I'll even pay for a more reliable Android app! Is there anything else out there?

There's an app called Rocket Track out there too, I have not personally tried it, but some people I know that have like it better than GPSRL.

Suggestion: Eggfinder App? We would pay $$$ for this. (at least I would)

Well, the LCD-GPS Module in the LCD receiver gives you the distance and the arrow/heading to get to your rocket, that's basically what you'd get with an app. And it doesn't require another device so it doesn't matter what's in your pocket. The problem with an app is that there are more pieces to maintain, and invariably if you have an app that talks to hardware there are going to be incompatibility issues at some point in the natural upgrade process. With everything in one box, all those issues go away.
 
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