The Eggfinder - A Low-Cost GPS/RF Tracking System

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Just in case if anyone was wondering you can certainly fit an Eggfinder and an altimeter in a 38mm thin walled nosecone.

It can certainly be done, this AV-Bay is going to have an attachment on the bottom that will hold the two batteries but it will work.

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That's a lot prettier than my 38mm NC mount... it's just a sled that fits into the NC, zip tied to the shock cord (which is epoxied into the NC) then sealed off with masking tape. I think somebody could make a bit of money by selling NC payload bays...
 
That's a lot prettier than my 38mm NC mount... it's just a sled that fits into the NC, zip tied to the shock cord (which is epoxied into the NC) then sealed off with masking tape. I think somebody could make a bit of money by selling NC payload bays...

Thank you for the compliment!

Someone is currently in the process of getting a better 3D printer and I may start selling different things I have in the works.

Does your sled hold just the Eggfinder and Eggtimer or the TRS?
 
It's a TRS in a RW 38 Special modified for DD. No motor mount, a 38mm motor fits great inside the FG thinwall tube. It's going to go up on an AT J270... OR sims it to about 11K. I'll be flying it at ROC this weekend.
 
Ditto, Doing my own 4 fin design with 38mm LOC tubes just to see if I can make fins stick to cardboard. Doing an upper bay with a TRS and will use a cable cutter for the main "unfurling". Kurt
 
I'm betting that you end up getting the LCD receiver. I know several people that are using the RX with Bluetooth and Rocket Locator, I've heard mixed things about it. It's always good to have a backup... and you CAN put a Bluetooth module in the LCD (although I recommend that you disconnect it temporarily when you're programming it).


What's the best way to switch the Bluetooth off? Just put a switch on the VCC / 3.3v wire?

I plan to use Bluetooth to log the flight on my laptop, so switching off the Bluetooth will also extend battery usage while out looking for the rocket.
 
What's the best way to switch the Bluetooth off? Just put a switch on the VCC / 3.3v wire?

I plan to use Bluetooth to log the flight on my laptop, so switching off the Bluetooth will also extend battery usage while out looking for the rocket.

A switch on the 3.3V line to the Bluetooth module would be fine. FYI, those things draw nearly 100 mA on their own, so turning it off if you don't need it is a prudent thing to do.
 
Anyone else having trouble connecting an eggfinder to a Windows 8.1 machine running Mapsphere? I have access to a mac it it's easier to use a mac.
 
I had trouble with Windows 8 for a LOT of things. Something about them changed the way drivers work and as a result, drivers that used to work with windows 7 will not work with windows 8.
 
I contacted Cris about a similar problem after upgrading my PC to Win 8.1.

He indicated that some of the older serial-to-USB cables would not work with Win 8.1. Suggest you contact him for details.

Erik
 
I contacted Cris about a similar problem after upgrading my PC to Win 8.1.

He indicated that some of the older serial-to-USB cables would not work with Win 8.1. Suggest you contact him for details.

Erik

Some of the issue is with the clone USB to serial chips. The drivers have been altered to nix counterfeit chips. Won't work unless you're able to roll back the driver. Same issue occurred with the Sainsonic AP510 GPS tracker. They had to ship a cable with a "good" USB to serial chip in the plug to get the thing to connect. FTDI got sick of their designs being copied.

MapSphere can get you a nice screenshot of a flight to the point of last packet reception, though it's no longer supported by the developers. That was confirmed to me by private email over two years ago. It's dead software.
Digging into it out in the field to get the last received lat/long value so one can input it into a handheld GPS to navigate to the last known packet/likely recovery site is tedious. Some of the map links are dead I think. At least they were a couple of years ago
the last time I tried it.

GPS rocket locator is sometimes squirrelly and it's best to have the LCD receiver for backup so one can input data manually into a mapping GPS to navigate to the rocket. Plus if one has a portable receiving station, it's easier to reacquire a new packet if the
last received position is not the final resting place. I will tell you, having an easy method to navigate to the rocket like GPS rocket locator is a cakewalk. Just follow from point A to point B on the screen.

I strongly suggest if you have rockets that routinely go "sight unseen" you have a portable receiving station that's easy to carry.

I was really getting fired up about using a laptop to store flights but I find it takes time to set the station up that would better be used for launching. Plus if you run into a setup bug in the field, you're in trouble.
If you are going to go the laptop route, practice relentlessly with your tracking software, how you are going to record, save the data or what have you. Know it cold before you get to the field. Or, simply use a portable receiving station
and fly more rockets. If you simply want to save a map with the rocket flight on it, you could use any APRS tracking program and plug/pair the EggFinder receiver in through the GPS port of your receiving program. ie. UI-View,
YAAC, Xastir or something else. Problem here is the learning curve of these programs would be very high for a neophyte. Kurt
 
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Anyone else having trouble connecting an eggfinder to a Windows 8.1 machine running Mapsphere? I have access to a mac it it's easier to use a mac.

You need the cable with the BLUE shell for Windows 8.x. Let me know if you have the older black one... we'll work something out.
 
It's not just this device, a lot of stuff stopped working in windows 8. I downgraded my computer back to 7 and couldn't be happier. Also Windows 8 seems more susceptible to spyware too
 
Chris-I would like to see a unit that also transmits on the 2 meter or 70
cm bands for hams who are also rocket enthusiasts. Also, will the unit transmit at least 100 milliwatts or even better near 1 watt (FCC approved LIMIT)?

Thanks,
Fred (KG4YGP)
Level 2 (acquired with the
support of cw bullet & the great members of
the orangeburg club!)
 
Chris-I would like to see a unit that also transmits on the 2 meter or 70
cm bands for hams who are also rocket enthusiasts. Also, will the unit transmit at least 100 milliwatts or even better near 1 watt (FCC approved LIMIT)?
Thanks,
Fred (KG4YGP)
Level 2 (acquired with the
support of cw bullet & the great members of
the orangeburg club!)

The market is likely not big enough to support the amount of work it would take to do that. Would take a major firmware update if not using the APRS mode. Would have to have a process to transmit the callsign periodically.
You can buy a variety of Beeline trackers currently in 70cm or 2 meter flavors. The Sainsonic AP510 transceiver on 2 meters is a candidate for large rocket tracking but would have to beware of the 500mw to 1 watt output and make sure it
wouldn't dork your deployment electronics. https://www.sainsonic.com/ap510-apr...tml?kpid=791&gclid=CJrV2N3ngsYCFdQ8gQod9IoAqA. Also support is nil with this device
and be prepared for a very high learning curve. The Sirf 4 chipset would not be reliable for absolute altitude reporting so the device would only be good to find the rocket. Tunable so one doesn't have to clog the 144.390 national APRS frequency.

Byonics had some lower powered APRS trackers out there in 300 to 400mW flavors but are no longer available. Again, one would have to cobble them together so if their skill set were limited, would be difficult.

APRS mode is good for once every 5 sec fix whereas due to the different encoding, the EF's will give a position 1/sec if there is a lock.

I can't speak for Chris but I don't think the market would be large enough to support a ham band, low powered GPS tracker designed expressly for rocket tracking. Of course, if the development costs were cheap, something might be forthcoming but
don't hold your breath

A lot of rocket folks were just "drooling" for an economical unlicensed GPS tracker that was cost effective that made the market ripe for the EggFinder. All the other 900Mhz stuff, except the Beeline GPS 900Mhz, was tied to a flight system and very pricey.

I will also point out again that more power is not necessarily better. Interference with one's deployment electronics can be more of a problem. I've had it happen and I've witnessed a devastating ballistic flight with a large dual altimetered project.
Kurt
 
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With the Eggfinder LCD starter kit, does it still come with an option to use a usb cord too? That way I could use either my phone gps or my laptop if necessary?
 
With the Eggfinder LCD starter kit, does it still come with an option to use a usb cord too? That way I could use either my phone gps or my laptop if necessary?

You can use the Eggtimer USB-serial cable connected to the programming/data header to stream the data to a suitable device, assumint it has a USB port. You can ulso use an HC06 or HC10 serial-Bluetooth module to send it to a device that supports a serial Bluetooth feed... lots of people use this in conjunction with Rocket Locator on Android. Apple doesn't support this directly... you'd have to write and app for it, but they don't support external GPS feeds so it's probably not easily doable.
 
Ok. Im thinking Ill get the bluetooth also. Im thinking Ill order the Eggfinder mini lcd starter kit. Ill have that Connor guy put it all together and include the bluetooth module. Am I correct in thinking with ordering all of that Ill be able to either
1) Enter gps coordinates that the lcd receiver gives me into my android phone, or
2) Track it via Bluetooth on android, or
3) Use Mapshere on my laptop.

Probably more money than I need to spend. But I like having options I guess. Does the starter kit come with a usb cord? Thanks for your help, Im just now trying to learn this all after finding out about it a few days ago.
 
Ok. Im thinking Ill get the bluetooth also. Im thinking Ill order the Eggfinder mini lcd starter kit. Ill have that Connor guy put it all together and include the bluetooth module. Am I correct in thinking with ordering all of that Ill be able to either
1) Enter gps coordinates that the lcd receiver gives me into my android phone, or
2) Track it via Bluetooth on android, or
3) Use Mapshere on my laptop.

Probably more money than I need to spend. But I like having options I guess. Does the starter kit come with a usb cord? Thanks for your help, Im just now trying to learn this all after finding out about it a few days ago.

Yes, yes and yes. Though Mapsphere can be tedious to extract the lat/long out of and you should practice with it like crazy if you are going to do it that way. I'd suggest you use the Android app "GPS Rocket Locator" and switch it to Open Source Maps
in the menu pulldown. It defaults to Google maps but they no longer work. You can cache the OSM maps at different zoom levels of your site and surrounding area and it's easy to walk and make the icons "come together"
If you have internet access onsite and your data charges aren't that bad you can track using the internet.

Me thinks Google gets pissy about people using and storing tiles off line and will eventually dork access so an app can't do that. Mapquest pulled its photomap tiles off for general app use last July.

Oh, Forget about live tracking on Apple phones. No app available there although there is an app Motion-X I believe one can manually input lat/long to find the position.

What do you mean more money than you need to spend! Five years ago you'd have to spend $700.00 on up to get a GPS tracker system for rockets. A bit cheaper for Ham APRS stuff but the 900Mhz stuff of which there were just a few systems could
hit $1500.00. Now is a great time to be able to fly out of sight with some reliable tracking onboard. Kurt
 
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No, I just meant more money adding on bluetooth, even though its like $15 dollars or something. Id like to have as many options tracking it out on the field in case one or the other doesnt seem to be working for whatever reason.

I was looking at dogtrackers and was thinking Im not ready to dish that kinda money out for my hobby yet. Then I found this and now Im already looking at kits that will reach a mile and I wont lose them. Im pretty excited.
 
Just installed rocket locator on my phone. Installed MapSphere last night on my laptop. Im all ready, time to order!
 
The setup I always use is the USB receiver on my laptop with Mapsphere for backup, and the LCD for portability. The laptop keeps track of the path of the rocket in case of an accident.
 
No, I just meant more money adding on bluetooth, even though its like $15 dollars or something. Id like to have as many options tracking it out on the field in case one or the other doesnt seem to be working for whatever reason.

I was looking at dogtrackers and was thinking Im not ready to dish that kinda money out for my hobby yet. Then I found this and now Im already looking at kits that will reach a mile and I wont lose them. Im pretty excited.

Be careful with dog trackers. Adept 22's will be dorked by them. They are on the MURS frequencies. Multi-Use-Radio-Service band and put out a whopping 2 watts. High Rf fields can dork deployment electronics but EggTimer stuff or
any device that uses Opto-Isolators on the deployment channels will be resistant to Rf interference. Still I'd test any unfamiliar installation with bare contained ematches on the outputs and stand the rocket out with everything on for
30 to 60 minutes. If the ematches don't pop or the altimeters down recycle or shutdown, one stands a good chance they'll work. Of course another reliable test is someone who's already flown an identical system successfully. That's
really good.

The EggFinder system is the most economical self contained system out there for sport flying period. Doesn't require a cell phone tower system to use. Yeah it has some limitations but it 's pretty darned good. Kurt
 
My mind is pretty much made up on the Eggfinder. Now I need to find a kit thatll go a mile up in the air. I mean, thats the whole point of me buying this stuff.
 
My mind is pretty much made up on the Eggfinder. Now I need to find a kit thatll go a mile up in the air. I mean, thats the whole point of me buying this stuff.

A Wildman Jr on J's will do the job. Would be easier to get an aftermarket longer von Karman nosecone to do a tracker mount there but I've crammed a Ham Beeline GPS in the ebay with a Raven II. Antenna goes through the forward bulkhead into
the main chute bay and the antenna is stented with a cardboard igniter tube that AT wired igniters come in so the wire doesn't get smushed. Over a dozen flights all but one sight unseen. Tracker found it every time. 5 to 6k on J's.
Kurt
 
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