Just cant get this Eggfinder to work right for me

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This thread has been a real eye opener for me. I built by eggfinder system a year ago but just recently started using it. I just thought I remembered everything in the manual. It's also good to hear about the different possible recovery outcomes that could affect gps results.



You may have lost signal at launch, then reacquired it during descent, then lost it before the actual landing because of terrain or the power lines. This last good fix was the one your wife recorded and resulted in a location where your rocket passed over but didn't come to rest.

It then sounds like you reacquired the signal when you continued walking to the actual landing site, but since you didn't check the coordinates displayed at this point you can not definitively say that you were getting erroneous data from your system. It sounds more like procedural issue.

I had this on the weekend.. I plugged in the coordinates I got when it landed and jumped in the car and head off. Left the LCD receiver (still beeping) in the car and walked into the field.. After 10mins of fruitless searching, walked back to the car, got the LCD out, input the coords and cursed as I thought the Apple maps had decided to give me the nearest road location... ignored it, input into google maps, got the same result.. walked to where it was telling me the rocket was, and sure enough it was there...

I've certainly updated my checklist for EFMini flights.

1) record (photo) launchpad location pre launch and check on the map to make sure it's where I know it is.
2) take more notice of the number of satellites the LCD is telling me the MINI has.
3) launch
4) when I see it land, take another pic of the coords on the LCD and PAY ATTENTION TO THE NUMBER OF SATS IT IS REPORTING
5) TAKE THE LCD WITH ME TO RETRIEVE...
6) When I get lost, recheck the LCD coords (take pics) and re-input into the GPS...

When @cerving announced the LCD-side GPS, I wondered what fool would need this frivolous extravagance.

Now, after two flights, realising how hard it is to see my iphone screen in full sunlight, am thinking about ordering one... ;^)
 
If the coordinates update on the lcd, shouldnt the location update on my phone at the same time?
 
You have to have an HC-06 or HC-05 bluetooth module wired into the Eggfinder LCD. You have to order that separately.
Next, you have to use another app to monitor the NMEA position stream. Your phone will not just "automatically" read the LCD.
There is no ideal tracking application available for these NMEA trackers yet.

The "best" tracking application would be a photomap with breadcrumbing. Breadcrumbing is a DOT or Square placed on the map to indicate the decoded position streaming from the tracker. In other words, each position you see flashing up on the LCD screen is placed on a map so you can visually look at it. I found that the best positions coming off an egg finder are when the rocket is under descent with a good main chute. These are the positions that would be nice to have plotted on a map to develop a drift trend.

I've been able to get close to that end but unfortunately using hacked ham radio software would be hard for the average person to set up.

As it stands none of the current tracking software easily available does breadcrumbing with NMEA trackers. An unsupported windows program called map sphere does some rudimentary breadcrumbing but there can be connectivity issues to a Bluetooth tracker. Plus, this program cannot keep track of your local position and do navigation.

Screenshot (48).jpg1.pngScreenshot (37).jpgScreenshot (21).jpgScreenshot (16).jpgScreenshot (4).jpgMapSphere.jpegtestcrossband.jpeg

These are a variety of tests and flights with different programs. There is a Mapsphere screen in there. If you can see the saved positions and develop a drift trend when the rocket is
coming in under the main chute (especially when it's down low) you might be able to overcome any spurious readings if the GPS antenna of the EggFinder is facing the ground and doesn't have a good view of the sky. I did a ballistic recovery with one or two positions placed on my map screen. I wouldn't have found the rocket easily without a map plot.
The tracker usually dies when it hits. Kurt
 
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I have the eggfinder connected to my phone with an hc06. Shouldnt it have updated the location on my phone if the coordinates on the lcd were changing? That is if they were, I dont recall.
 
I have the eggfinder connected to my phone with an hc06. Shouldnt it have updated the location on my phone if the coordinates on the lcd were changing? That is if they were, I dont recall.

Ideally yes, but I've seen Bluetooth connections drop. They're only good for about 30', so I've seen people walk away from the receiver with their phone and when they get back they've lost their pairing. That's the beauty of the new LCD-GPS Module... it's built into the LCD receiver so it's always there, and it performs essentially the same rocket finding function as one of the navigation apps. You don't get the the pretty map, though, but you can add a Bluetooth module and pair it with your phone if you want that... if you lose the Bluetooth connection you haven't lost your rocket, just the pretty map.
 
Ummmmmm, it's called backup which is a good thing. B/T is good for 30 feet on a good day. Am lucky to see 10 to 15' with a Trackr device: https://www.thetrackr.com/bravo/?gc...En6ozbSk-5HfAKmorU9Xz3bc2pesDPxRoCMx4QAvD_BwE


They claim 100 feet but that's a bunch of hooey. I'm lucky to get 10 feet indoors with car keys. Nonetheless I find it useful when I misplace 'em indoors. I can walk from room to room and can find the keys pretty easily.
Same thing goes with the cell phone if it's turned on and I have my keys. Push the Trackr button and the phone beeps.

If the EF ends up with a less than optimal fix, 3 satellites and 110 feet, the arrow might start jumping around like crazy. I've not had that happen out in the field myself but have seen that with indoor testing and a lousy constellation configuration.
I take the tracker outside and all is well.

Using a map is nice but if one has a 5 to 6 or more satellite fix, the arrow should work pretty well. I gotta start building my GPS add-ons tonight. Got my two LCD's software updated already.
Remember to use a beeper for high vegetation. A 140dB job might not be needed but a "quieter" one could be helpful for close in homing. Creeeeeipes. with 140dB why do you need an Rf tracker at all?:grin::grin: Kurt
 
I have an Eggfinder that I've used for 3-4 flights, and I've been very happy with it. But, I did find out something when I tried to match up the readings I got from the Eggfinder with my Magellan 315. Before my first launch with the Eggfinder, I got the readings from it's current position, and the Magellan unit. They did not match, there was a difference of about .33 units on both the latitude and longtitude. I just made a note of this, and used it accordingly. I figures the Eggfinder was probably the more accurate unit, as it is newer, the Magellan is probably 20 years old. I should point out that the .33 difference is on the seconds part of both the Lat. and Long. It's really not enough to be a problem, I just set off the direction of flight, and listen for the beeps, when they get more frequent, I can usually see the rocket.
I suspect there may be differences is these units due to age, and possibly out of date "software" in the Magellan.
Not sure if this helps or not, but there you go.

Phil L.
 
I don't have an Eggfinder, but have had some recent problems with another vendor's 900MHz GPS unit. Outside of needing to have lock on a good number of satellites, one thing I saw mentioned in this thread is a default by one of the Maps apps to report a "nearest road" location versus the true GPS coordinates. Looking back, I believe in my last two incidents, this is part of what "bit me." I believe these mapping apps, in a race for usership, are becoming "too smart" and screwing with some of us hobbyists (i.e., geocaching, HPR, etc.). As a result I have sworn off the phone based apps and purchased a Garmin eTrex 30x a couple of months ago. Certainly not high end, but adequate for what I need and will help me eliminate one other downside factor in rocket retrieval.
 
I noticed that for my last TRS flight, the LCD displayed an asterisk for the number of satellites in view. I assume that this means the number was greater than 9 and the display is not set up for 2 digits, so it just displays "*". I looked at the manual and did not see anything on this.

Cris?
 
I noticed that for my last TRS flight, the LCD displayed an asterisk for the number of satellites in view. I assume that this means the number was greater than 9 and the display is not set up for 2 digits, so it just displays "*". I looked at the manual and did not see anything on this.

Cris?

You are correct > than 10. Kurt
 
I don't have an Eggfinder, but have had some recent problems with another vendor's 900MHz GPS unit. Outside of needing to have lock on a good number of satellites, one thing I saw mentioned in this thread is a default by one of the Maps apps to report a "nearest road" location versus the true GPS coordinates. Looking back, I believe in my last two incidents, this is part of what "bit me." I believe these mapping apps, in a race for usership, are becoming "too smart" and screwing with some of us hobbyists (i.e., geocaching, HPR, etc.). As a result I have sworn off the phone based apps and purchased a Garmin eTrex 30x a couple of months ago. Certainly not high end, but adequate for what I need and will help me eliminate one other downside factor in rocket retrieval.

For about 99% of rocket retrieval cases, just knowing the distance and which direction it's in is good enough. I've never used maps on my iPhone with MotionX, the vector arrow works fine. That's the same as the Eggfinder LCD-GPS... if you know how far it is from "you" and which direction is is from "you", it doesn't matter which path you take to get to it (roads around it, desert path right to it) you're going to end up at the same place... where your rocket is.
 
For about 99% of rocket retrieval cases, just knowing the distance and which direction it's in is good enough. I've never used maps on my iPhone with MotionX, the vector arrow works fine. That's the same as the Eggfinder LCD-GPS... if you know how far it is from "you" and which direction is is from "you", it doesn't matter which path you take to get to it (roads around it, desert path right to it) you're going to end up at the same place... where your rocket is.

True. The only problem is the case where the satellite lock is lost with the GPS antenna is pointing towards the ground during the lie as a fellow previously posted. Personally, I think that outcome is pretty rare as I've never had it happen and cripes I and others have done totally ballistic recoveries (not by choice mind you!:facepalm:) by going to the last known position and there's the fincan sticking up.

In the case where the rocket is in vegetation, with a lousy lock and no onboard screamer, a map display that gives the last "good" known position 50 to 100 feet in the air could give one a decent clue as to how to proceed.

I had the experience of standing right where the EF was telling me where the rocket was supposed to be in a no till cornfield and nada. I looked at the position on the LCD and my local position and scratched my head.
Nice beeping positions coming in too. The corn was in but the rocket was camouflaged in the chopped off stalks. Chute couldn't get out of the protector so it was no help.
I had a live map and stupidhead zoomed it in, walked twenty feet and there it was. Was a glass rocket so no harm done and it gets to fly again.

Out in the open and it's not so much of a challenge. All can take solace in the fact of a bad "lie" on the ground is not that frequent of event.

Heck, I've not seen anyone post anything of this nature with the APRS rocket trackers out there though I don't believe as many people were flying them due to the cost in the bygone days. Kurt
 
For about 99% of rocket retrieval cases, just knowing the distance and which direction it's in is good enough. I've never used maps on my iPhone with MotionX, the vector arrow works fine. That's the same as the Eggfinder LCD-GPS... if you know how far it is from "you" and which direction is is from "you", it doesn't matter which path you take to get to it (roads around it, desert path right to it) you're going to end up at the same place... where your rocket is.

Does the new lcd gps have to be soldered or can I just remove the old one and plug in the new one?
 
Does the new lcd gps have to be soldered or can I just remove the old one and plug in the new one?

There is no GPS in the EggFinder LCD receiver. This is an add-on.

Cris is out west and us flatlanders in the Midwest have a lot of obstacles to negotiate in the farm land. If one has a map overview of a flight here they instantly can see what they have to go through or around. True, one can input the data into a phone or GPS and get an idea of the last known position but a live representative overview on a photomap of the rocket flight, especially the drift trend line down low, can be very helpful if the rocket isn't seen where you think it should be. That said, I got two of the GPS addons and have one on the Black Aero case and intend to mount one on a stock LCD black case. I did some cursory testing and it goes without saying one needs to be outdoors to test this and it gets more accurate as one is moving towards the tracker.
It should be understood that after the firmware update the user can scroll with the push button the tracker lat/long
HDOP, distance and number of satellite lock screen and one push takes one to the "position/navigation to" screen
using the SirfIV Maestro GPS mounted in/on the EggFinder LCD device. I recommend it.
If one wants to track with arrows alone without any other hardware it's perfect for that.
If one wants to use it for backup to GPS Rocket Locator (or any other terminal software), they can do that too as long as an HC-06 or HC-05 B/T module is installed. In that case, your Android devices GPS is being used
as the local position for GPS Rocket Locator and the EggFinder LCD/GPS addon is basing it's directions on the case
mounted Maestro GPS. Kurt
 
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