Rocket Track - Open Source GPS Tracker for Smartphones

the model rocket show
Advertise with us
Shop deals on ebay
The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
WoShuGui said:
My problems with damaged components has been more insidious. I have one Tx unit that flat spin fell in a nose cone from 3,500' that still seems to work. The lights blink, but compared to my other units, it takes much longer to GPS lock and the RF range is extremely short. At one point the regulator failed and had to be replaced, so something is amiss; and it is still very flaky. Not sure if the problem is the GPS, XBee, both GPS and XBee or something else. Another unit got the duck antenna connector on the XBee bent when I pushed too hard into a nose cone. That one has less range as well compared to my third Tx. Has anyone else seen variations in range among units? I have verified all Tx are operating at the same transmit settings. I am thinking to try replacing the XBee to see if that helps.
Click to expand...

the one where the gps takes longer to acquire a lock seems like the gps is bad. That could be causing issues with the voltage regulator. What is the voltage on that board?

The second one seems like a broken etch or solder joint on the antenna trace on the xbee. replacing the xbee should fix that.
 
Derek said:
It sounds like either the gps or tx xbee radio is dead. Do the lights on the tx still light up and flash? Is there any obvious damage to the tx?

If the lights come on and flash, I'd suggest trying to connect to the tx xbee radio using the latest x-ctu program. That will tell you if the xbee is ok. Also, check your solder joints again. It is possible you had a cold solder joint and the extreme ejection charge opened it up.

Derek
Click to expand...

if the gps was dead, how could it find me on the map?
the only thing that doesn't work is satellite fix and lattitude & longitude positions
 
your position is determined by the phone's gps.

edit:
do you see any data coming in on the console tab on the rocket track app?
 
Last edited:
No. I thought if I had location turned off on my cell phone it wouldn't pick up my location.
It might be using my wi-fi for location I'm guess.
There is no data coming in on the console [other than "connect ed to rx]
 
I don't think the app will run if you don't have location services on. At least it didn't for me when I just tried it.

Since you aren't getting any data in, it could be either the gps or the tx xbee. can you talk to the tx xbee through the rx with xctu?
 
attached the xctu to the xbee and then to usb.
power light on the xctu is red, red led on tx board is solid red, green led is blinking.
tried a "test/query" and modem "read parameter", both fail communication with modem. (115200 baud and 9600)

I'm assuming it's dead
what's the easiest way of removing the xbee from the board?
 
6x6 said:
attached the xctu to the xbee and then to usb.
power light on the xctu is red, red led on tx board is solid red, green led is blinking.
tried a "test/query" and modem "read parameter", both fail communication with modem. (115200 baud and 9600)

I'm assuming it's dead
what's the easiest way of removing the xbee from the board?
Click to expand...

did you swap the power and activity leds when you built it? did you open the two solder joints on the tx?

if you have bluetooth on your pc, you should be able to connect use the rx to talk to the tx over the air.

I use solder wick to remove xbee modules. two soldering irons help, too.
 
Are you talking about sJ1 and sj2?
Do they need to be open?

just tried again (red led blinking, green solid. my bad)
opened sj1 and sj2, same results (have I screwed up the gps now, testing with the joints closed?)

1408117221449.jpg
 
Last edited:
sj1 and sj2 need to be open if you want to use the usb to serial cable on the tx. the gps should be fine with them closed for a short period.
 
I was using the USB to xbee adapter, would that make any difference?

1408120542870.jpg
 
oh, no. I misunderstood you and thought you were using the usb to serial cable plugged into the header on the tx. sorry.

you should still open sj1 and sj2. xctu has a problem with it receives data it wasn't expecting. opening up the jumpers prevents that from happening.

there is a command you can send the gps that accomplishes the same thing, but opening the jumpers is easier.
 
Derek said:
I don't think the app will run if you don't have location services on. At least it didn't for me when I just tried it.

Since you aren't getting any data in, it could be either the gps or the tx xbee. can you talk to the tx xbee through the rx with xctu?
Click to expand...

Got the new xctu software. For those who want to forgo the learning curve, here are some screen dumps and instructions to verify "remote" xbee communication and firmware updates.

1. attach an xbee to PC/laptop with the new XCTU software, have it locate the modem and set "AP Enable" to "API Without Escapes [1]". (first pic)
2. On the left column is the Radio Modules it has located, to the side of the information is 3 buttons, the middle one is "discover radio nodes in the same network".
Turn on another xbee you want to control and click the "discover" button. (pic 2)
3. After it finds the new modem on the network, make sure it is "checked" and select "add selected devices" (pic 3)
4. From the "radio modules" on the left column, choose the new "remote" module. It will load the settings. If you want to update firmware, click the appropriate button on the top. (pic 4)
5. A pop up window will show the different firmware versions to choose from. Choose a firmware and click "finish". It will load the new firmware and you're done. (pic 5)

xctu-1.png
xctu-2.png
xctu-3.png
xctu-4.png
xctu-5.png
 

Attachments

  • xctu.png
    xctu.png
    83.4 KB · Views: 115
Last edited:
I'm not 100% sure, but I think I used with escapes but I think it worked both ways.
 
Which firmware is the Pnt2Multipoint? I want to change mine from Digimesh to Pnt2Multipoint.
 
the one that has 10k in the description.

edit:

thanks to the excellent pics posted by 6x6 above, you can see the digimesh and point to multipoint fws. In the last picture under the product family column, digimesh fw is called XBP9B-DM and the point to multipoint fw is called XBP9B-DP.

Thanks 6x6!
 
Last edited:
I updated post #5 with links to OSHPark so you can purchase the boards directly from them.
 
Derek said:
Since you don't have the 6-pin headers installed you need to close sj1 and sj2, which it looks like you did.

1.2 ohms doesn't sound right. I get about 50k ohms on my rx. Your voltages looks right so I'm guessing your 1.2 ohm reading is wrong.

Also, don't power it up without the antenna installed.
Click to expand...

What happens if you power up the TX or RX without the antenna?
 
6x6 said:
What happens if you power up the TX or RX without the antenna?
Click to expand...

I think it's unhealthy to the power output transistors if there isn't a load. Some might be able to stand it, some might be damaged. At lower power
they stand a chance to survive. If you do it by accident, the only thing you can do is a range check. If it's dorked, the transmitter module will need to
be swapped out. (Pricey amplifiers have fold back circuits that cut the power to avoid damage but that's not likely at this level.) Kurt
 
ksaves2 said:
I think it's unhealthy to the power output transistors if there isn't a load. Some might be able to stand it, some might be damaged. At lower power
they stand a chance to survive. If you do it by accident, the only thing you can do is a range check. If it's dorked, the transmitter module will need to
be swapped out. (Pricey amplifiers have fold back circuits that cut the power to avoid damage but that's not likely at this level.) Kurt
Click to expand...

Range check? Does that mean verify how far the transmitter and receiver will talk to each other?
Or check to see if they communicate period, regardless of distance.

I never knew this was an issue and I've been ground testing multiple times without attaching the antenna on either one, TX and RX.
Now I'm thinking I might have broken something. :bang:
 
6x6 said:
Range check? Does that mean verify how far the transmitter and receiver will talk to each other?
Or check to see if they communicate period, regardless of distance.

I never knew this was an issue and I've been ground testing multiple times without attaching the antenna on either one, TX and RX.
Now I'm thinking I might have broken something. :bang:
Click to expand...

Receiver shouldn't be a problem whatsoever. Range check is set the transmitter down or up somewhere and walk away with the receiver and see how far you can go before you lose a valid data transmission of lat/long. It would be nice to have flat open ground to do this.

As I said, with a lower power transmitter it may not be as much of a problem so don't despair. Just test and be certain. I launched two flights with GPS trackers on the 70cm band inside metallic painted rockets without an adequate range check and found out the hard way that wasn't the right thing to do.
One had a recovery failure and went in ballistic (not the trackers fault) and the other came back from 10k' within eyeshot so recovery wasn't a problem. Only one packet was received from the 10k' rocket. 200 feet range was no problem but any farther than that was no good.

If you're 1/4 or 1/2 mile away with your tracker lying on the ground, I'd say that's pretty good ground range. You got the transmitter upright, waist high
and are farther out, you should be good. I've gone so far now as testing the transmitter inside the carrier/nosecone for the range check to be certain I have the range and avoid metallic paint. Also, if one is going to have the tracker ride in the ebay, best to test with bare ematches on the ground to make sure the tracker won't dork the deployment altimeter(s). Rf can do strange things to electronics. The low powered Beeline trackers play well but going to 100mW or above one should be cautious. A couple of years ago and 16 foot 12 inch diameter O powered rocket went in ballistic when a 2 watt Garmin dog tracker gorked both deployment altimeters. Kurt
 
Last edited:
ksaves2 said:
Receiver shouldn't be a problem whatsoever.
Click to expand...

The problem with that is these are transceivers. I'm pretty sure there is some bidirectional communication when powered up to establish the link.
 
Derek said:
The problem with that is these are transceivers. I'm pretty sure there is some bidirectional communication when powered up to establish the link.
Click to expand...

Well in that case, one would want to make sure they have an antenna on it at all times if both sides of the devices are in use with bidirectional communications active.
If they've been run without antennas, I say do a ground distance test and if a reasonable range is seen, would be ok to fly.
I don't know what advantage there would be with two way communication between the units. The EggFinder unit uses Hope transceivers but the transmitter uses the transmitter side and the receiver uses the receiver side of the board. Kurt
 
Is there a way to make the RX have an LCD for tracking so I don't have to use a PC/Laptop. I use IOS device and shame I can't get them to talk
 
Pyropetepete said:
Is there a way to make the RX have an LCD for tracking so I don't have to use a PC/Laptop. I use IOS device and shame I can't get them to talk
Click to expand...

sure. you'll need something like an arduino, a lcd screen and a bit of programming.
 
You can save yourself a bit of work if you get an Eggfinder LCD receiver without the Hope RF module (yes, you can order it that way), and wire in an XBee instead. As long as the XBee talks at 9600 baud it will work, the processor is just looking for a 9600 baud NMEA data stream. The only output to the Hope RF module is for programming the frequency, and you're not going to be doing that so you only need 3 wires between the XBee and the board: +3.3V, GND, and RXD.
 
cerving said:
You can save yourself a bit of work if you get an Eggfinder LCD receiver without the Hope RF module (yes, you can order it that way), and wire in an XBee instead. As long as the XBee talks at 9600 baud it will work, the processor is just looking for a 9600 baud NMEA data stream. The only output to the Hope RF module is for programming the frequency, and you're not going to be doing that so you only need 3 wires between the XBee and the board: +3.3V, GND, and RXD.
Click to expand...

there you go. that is a much simpler solution.
 
Pyropetepete said:
Umm. So the lcd reports what exactly]
Click to expand...

Here is a quote from the Eggfinder site about the LCD:

The Eggfinder LCD is a handheld portable receiver with a LCD display for the Eggfinder system, it makes using the Eggfinder system a snap. You simply turn it on, and as soon as it picks up the signal from your Eggfinder TX transmitter with a valid GPS fix it displays the following information on the display:

o Latitude and Longitude
o Number of satellites used in the fix
o A bar graph that shows you the quality of the fix, based on the Horizontal Dilution of Precision (HDOP)
o The number of seconds since your last good fix, useful if you lose the signal
o The last GPS altitude (not necessarily your rocket's altitude... GPS altitude tends to lag somewhat)

Using the Eggfinder LCD is easy. You take the last latitude and longitude fix from the display and enter it into your smartphone's navigation app, then you tell you app to navigate to that point. It works with any GPS-enabled smartphone, and it will work with handheld GPS devices like those made by Garmin and Magellan too. You can also connect a HC-06 type Bluetooth module (not included) to it so you can get real-time tracks from your Windows or Android device without having to type in the coordinates.

o Latitude/Longitude can be displayed in Degrees, Degrees:Minutes, or Degrees:Minutes:Seconds
o Altitude can be displayed in Feet or Meters
o Programmable frequency selection, so you can use it with any Eggfinder TX transmitter
o 16x2 LCD display, black-on-yellow for high visibility in any lighting condition
o Yellow backlight for those brave rocketeers who may want to use it for tracking night flights (with optional switch)
o Beep indicator tells you audibly when you have a fix, so you don't need to keep looking at the display
o 1/4 wave "stick" antenna included... pads provided for RP-SMA connector for optional external antenna to extend range
o Connector and space for optional HC-06 Bluetooth module, for easy real-time interfacing to Windows/Android devices
o Firmware can be field updated for new feature support
o Kit includes all parts, a case, mounting hardware, and a 4xAA battery box with switch... just add batteries and you're ready to go
Click to expand...
 
cerving said:
You can save yourself a bit of work if you get an Eggfinder LCD receiver without the Hope RF module (yes, you can order it that way), and wire in an XBee instead. As long as the XBee talks at 9600 baud it will work, the processor is just looking for a 9600 baud NMEA data stream. The only output to the Hope RF module is for programming the frequency, and you're not going to be doing that so you only need 3 wires between the XBee and the board: +3.3V, GND, and RXD.
Click to expand...

So one simply would have to look at the pads on the EF LCD board and look at the Hope-TRP module spec sheet: https://www.hoperf.com/upload/rf_app/HM-TRP.pdf to attach the XBee. Looks simple enough to do. RXD from the XBee to RXD on the EF receiver board along with the ground and VCC +. Couldn't be any easier if you ask me. Kurt
 

Similar threads

Adrian A
New Featherweight GPS phone app available for Android and iOS
2 3
Replies
73
Views
6K
jgarbus
J
F
Using two FeatherWeight Trackers with one Ground Station
Replies
9
Views
576
Adrian A
Adrian A
Buckeye
GPS Connector: Another Android Bluetooth app for Missileworks and Eggfinder GPS
Replies
19
Views
2K
Buckeye
Buckeye
stevemco
Sold Apogee Components Simple GPS Tracker $250
Replies
2
Views
401
stevemco
stevemco
beretta
BMP390 pressure sensor interference with telemetry
Replies
4
Views
447
jderimig
jderimig

Latest posts

Back
Top