Eggfinder LCD - Handheld Display Receiver for Eggfinder GPS Tracker

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Nice case. Do you have a manufacturer/part no.?

Love the logo too. I've been dabbling with some Eggtimer Rocketry logos to brighten up the web site, but I'm a lousy artist...

Cris it's the same case I bought. I have posted the link a couple of times on this thread, its made by Hammond part # 1553TBK
 
Oh, it looked a little different. Too bad those run almost $15, I'd love to include them with the kit, but they're just too expensive. I go for low price over style... never learned the Apple lesson, I guess.

Cris it's the same case I bought. I have posted the link a couple of times on this thread, its made by Hammond part # 1553TBK
 
Oh, it looked a little different. Too bad those run almost $15, I'd love to include them with the kit, but they're just too expensive. I go for low price over style... never learned the Apple lesson, I guess.

I think it's because Ringo's came out better and it has that cool logo on it. I think I am going to order a logo from Stickershock unless you come out with an official one. The reason I bought the case was so it fits more comfortably in my hand. I am going to use the square enclosure to make a wireless launch controller powered by a 3s Lipo.
 
Finally got around to building my EF LCD yesterday. Did the stock case friday and soldering yesterday.
Works and I flashed to 1.06.

IMG_20140802_191305.jpg


IMG_20140803_173507.jpg

After I put a toggle switch on the top for the backlight
The left side toggle is a locking switch I got from Electronics Goldmine some time ago for about $3.00. Now
I can't find them for this price anywhere. It locks on or off my by pulling on the spring loaded lever.


IMG_20140803_173538.jpg

The HC06 is seen double stick taped to the 1500Mah 2C lipo. There is a 3000mah cell out there for $18.00 that is the same size but is thicker. Plenty of room in the stock case. I used the ribbon cable mentioned here previously.
The battery is velcroed in and I used some screw terminals on the RST (for flashing), programming button and battery terminals for ease of connection. I got a bulkhead connector for the antenna from ebay. Kurt
 
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Recharged the batteries on both my Eggfinders and cycled them on to make sure they got lock. Went to install the magnetic base antenna on the LCD RX and discovered the connector doesn't fit the RX board. Rather than try to find an adapter, I cut the end off the coax and spliced a new connector on from a short coax I had. Got good signal from both transmitters, so the splice must be good. Will be doing a distance test tomorrow.
 
Wayne, I'm interested in conducting my own distance test. Please post your procedure.
 
Probably won't happen today, we just finished doing ejection charge tests on Sharon's Stinger. I don't thing the little dog next door will ever be the same. 3.1 grams for the drogue!
My plan is to fire up the TX and put it out on top of our kiva, about 6 ft. up. We live on a golf course, so it's wide open out there. Put the magnetic base antenna, which is theoretically a 16dbi omni-directional design on the roof of the truck and go for a drive. We did this with the rubber duckie antennas and got over 1/4 mile, and that was with the RX inside the truck. It will be just a comparison to the results from that test. Might get to it tomorrow, things are busy here with the prep for Airfest, we are leaving next Tuesday.
 
Probably won't happen today, we just finished doing ejection charge tests on Sharon's Stinger. I don't thing the little dog next door will ever be the same. 3.1 grams for the drogue!
My plan is to fire up the TX and put it out on top of our kiva, about 6 ft. up. We live on a golf course, so it's wide open out there. Put the magnetic base antenna, which is theoretically a 16dbi omni-directional design on the roof of the truck and go for a drive. We did this with the rubber duckie antennas and got over 1/4 mile, and that was with the RX inside the truck. It will be just a comparison to the results from that test. Might get to it tomorrow, things are busy here with the prep for Airfest, we are leaving next Tuesday.

Wayne, If you're using that antenna I posted the link to, I apologize, I thought I posted the one for the RP-SMA connector. I use the plain SMA connectors because
I already have a supply of them at home. Were you able to dig the magnet out of that stupidly weak magnetic base and come up with something different to secure it to your truck?

In a city environment with obstructions, I easily got .30 mile and the signal was still strong with that long receive antenna. I plugged the EF receiver into a laptop and had Xastir digipeat the EF transmitter positions on 144.800 which I read on a D72A while I carried the EF transmitter with me. I had the laptop with the EF receiver in my SUV in the driveway at home with a long 900Mhz antenna on the roof with a 2m antenna to digipeat the incoming position. The LCD version wasn't available at the time when I did the test so I did it backwards since I didn't want to carry a laptop with me. The only thing I would have been able to tell was if the packets dropped out, I would have known I was out of range. I read the range off the Xastir map when I got back from the hike. I ran out of time so I couldn't take it to the limit of the range.

Much easier with the LCD as one can put the transmitter in a nice stationary spot and get all the information off the LCD and monitor the piezo beeps while moving away. I suspect you'll get a pretty decent range, maybe even a mile or more, as long as there is a line of sight to the transmitter. You'll be set for that L3 attempt if you didn't already fly it. Kurt
 
I found some rare earth magnets on e-bay that are flat rectangles 3" long and 1/2" wide. They are only 1/16" thick but very strong. Once they decided which way the flux lines on the donut magnet in the base of the antenna went, they latched on tightly. When I put the antenna on the truck, you can still pull it off, but it's hard to do, and the magnets stay on the truck. I think it will work for driving down the dirt roads around Airfest.
Don't worry about the antenna, I think it did say RP-SMA, but you know how some of the vendors are, they probably don't know the difference. I'm just surprised I could splice the right connector into two different types of coax and have it work. I'm sure there is some loss, but we will see when I do the test.
 
I've discovered an interesting add-on that allows me to "connect" an external B/T GPS to my Nexus 7 Flo (no cellphone inside)

https://play.google.com/store/apps/details?id=googoo.android.btgps&hl=en

I've unlocked and rooted my device and allow mock GPS provider in the setup. What this allows me to do is route the incoming position
stream from the EF GPS transmitter through the EF LCD with the B/T module to the Nexus 7 and scroll through the position, satellites and when I have Wifi, get a map that shows where the EF is located. It will temporarily subvert the internal GPS of the N7.
I don't think it will help with tracking because one is just looking at the EF position and the position of the device is not on the display at the same time. One can just shut down the program and go back to the internal GPS on the phone/device and fire up Rocket GPS Locator to get both positions on the display.

The other thing I can do is since I'm a ham, I can gate the EF position to the APRS network by firing up APRSIS DR. It will use the position coming in from the EF LCD to put the APRS position on the network.

Ok, one could monitor the satellites in view from their Android cellphone/device but can actually see what is being used for position reporting by the EF GPS transmitter. It's kind of a nice option to have with the rocket on the pad to see how many satellites the device has a lock on. Can then exit out and fire up the GPS Rocket locator to track the flight. Kurt

Have since upgraded to a 2100mah pack:

https://www.hobbyking.com/hobbyking/store/__8272__ZIPPY_Flightmax_2100mAh_2S3P_Receiver_Pack.html

Fits above case just fine.
 
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Did a transmitter runtime test Sunday. Stuck on dashboard in car while I did work at the office. Used a 7.4V
1500Mah Lipo that was balance charged. Ran it for 6 hours, put it back on the charger and FWIW got 357 mah
for recharge/consumption. Not bad. Kurt
 
It's a bit long, 17", so it might not be suitable for the transmitter. It would be OK for the receiver, though. L-Com is a well-respected brand in the communications field, so you can be pretty sure that the specs are accurate.
 
I am not a very experienced solderer, but im going to get the LCD starter kit and give it a try. Does anyone have link for a good rubber ducky antenna for the transmitter and maybe a larger more effective one for the receiver that is still portable. I know nothing about antenna's. Especially if there are good or bad brands out there. I am going to be flying some 10,000 ft rockets but would like to try it on a 25k or 30k rocket.
Also with DBI, am I understanding that the higher the DBI the more directional it is, but more powerful in the directions it does point. And if that is true how can you have a high DBI have a omnidirectional antenna? Are the fields that it can receive very narrow but arranged in multiple directions? Just trying to optimize my range without becoming a directional antenna.
 
It's a bit long, 17", so it might not be suitable for the transmitter. It would be OK for the receiver, though. L-Com is a well-respected brand in the communications field, so you can be pretty sure that the specs are accurate.

Thanks for the info. I think I'll go with the smaller 3db for the transmitter and the 17'' for the Rx. Here is the smaller version for anyone interested:
https://www.l-com.com/wireless-antenna-900-mhz-3-dbi-rubber-duck-antenna-rp-sma-plug-connector

I just complete my transmitter today and it turns on like a champ. It did take 5 hours because I am not very good at soldering. I'll be working on the Rx tomorrow :D!
 
You can think of an antenna as being like a round balloon, with the radius from the center as the signal strength in that direction and the volume of air representing the total RF power. If you squeeze the balloon in one direction, it gets longer, but it gets narrower in the other directions since there's only so much air (signal) to go around. If you flatten the balloon out like a donut, that's a typical omnidirectional antenna. If you flatten it out like a pizza, that's a high-gain omnidirectional antenna: lots of gain in every direction around the center, but narrower beamwidth. If you stretch it out so it's long and narrow, you get a whole lot of signal in one direction, and nothing in the others. That's a panel, Yagi, or dish, depending on how skinny and long you squeeze the balloon.

This is an oversimplification, of course, but it's an easy visualization of how antennas work...
 
Thanks for the info. I think I'll go with the smaller 3db for the transmitter and the 17'' for the Rx. Here is the smaller version for anyone interested:
https://www.l-com.com/wireless-antenn...plug-connector

I just complete my transmitter today and it turns on like a champ. It did take 5 hours because I am not very good at soldering. I'll be working on the Rx tomorrow

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5 hours? That's not bad at all! Especially if unfamiliar with the components and soldering. When it fires up first time and the packets come streaming in after a few minutes of getting a fix, (flashing yellow LED) you're in the catbird seat. On the receiver, you might want to cut the holes in the box first and when you get it done, fire it up before mounting it and see if it's the 1.6 firmware. If you just received the kit recently it probably is the latest. Look at it this way, you'll be ready to build a second transmitter for another rocket so you don't have to swap it out if you want. Kurt
 
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5 hours? That's not bad at all! Especially if unfamiliar with the components and soldering. When it fires up first time and the packets come streaming in after a few minutes of getting a fix, (flashing yellow LED) you're in the catbird seat. On the receiver, you might want to cut the holes in the box first and when you get it done, fire it up before mounting it and see if it's the 1.6 firmware. If you just received the kit recently it probably is the latest. Look at it this way, you'll be ready to build a second transmitter for another rocket so you don't have to swap it out if you want. Kurt

Great idea! I just mapped out my cut marks and holes to do in the AM. However I do have a noob question. What is the difference between RP-SMA Plug and RP-SMA Male? I just realized that both antennas have the RP-SMA plug with no male option.

Thanks!
 

That is not an RP-SMA connector

An RP-Connector has the pin in the jack and the female portion in the plug. If you buy an RP-SMA connector from Cris, you will get something like this:

https://www.ebay.com/itm/like/301285534165?lpid=82

You'll need an antenna like this for an example: https://www.ebay.com/itm/GSM-Omni-A...ectional_Network_Antennas&hash=item233b45efdf

I had edge connectors like this lying around: https://www.ebay.com/itm/10pcs-Conn...Coaxial_Cables_Connectors&hash=item3f293ef5c9

Which is just the opposite of the RP-SMA jack.

So I had to use the antenna with the pin in the middle like this: https://www.ebay.com/itm/2pcs-Anten...pt=US_Radio_Comm_Antennas&hash=item3f28bf434d

The bottom line is you have to match the antenna to the Jack. RP-SMA and SMA are different. So whatever gender jack you use (RP = pin in jack) one needs to get the appropriate antenna or cable.

I have a patch antenna and I got a gender changer so one could plug my cable to that antenna into their RP-SMA jack so they could borrow it. Kurt
 
That is not an RP-SMA connector

An RP-Connector has the pin in the jack and the female portion in the plug. If you buy an RP-SMA connector from Cris, you will get something like this:

https://www.ebay.com/itm/like/301285534165?lpid=82

You'll need an antenna like this for an example: https://www.ebay.com/itm/GSM-Omni-A...ectional_Network_Antennas&hash=item233b45efdf

I had edge connectors like this lying around: https://www.ebay.com/itm/10pcs-Conn...Coaxial_Cables_Connectors&hash=item3f293ef5c9

Which is just the opposite of the RP-SMA jack.

So I had to use the antenna with the pin in the middle like this: https://www.ebay.com/itm/2pcs-Anten...pt=US_Radio_Comm_Antennas&hash=item3f28bf434d

The bottom line is you have to match the antenna to the Jack. RP-SMA and SMA are different. So whatever gender jack you use (RP = pin in jack) one needs to get the appropriate antenna or cable.

I have a patch antenna and I got a gender changer so one could plug my cable to that antenna into their RP-SMA jack so they could borrow it. Kurt

Ok so before I saw your post, I ordered the following:
https://www.l-com.com/wireless-antenna-900-mhz-5dbi-rubber-duck-antenna-rp-sma-plug-connector
https://www.l-com.com/wireless-antenna-900-mhz-3-dbi-rubber-duck-antenna-rp-sma-plug-connector

I also ordered the RP-SMA connector from Cris.

So what jack would I need to order to get these antenna to work?
 
Ok so before I saw your post, I ordered the following:
https://www.l-com.com/wireless-antenna-900-mhz-5dbi-rubber-duck-antenna-rp-sma-plug-connector
https://www.l-com.com/wireless-antenna-900-mhz-3-dbi-rubber-duck-antenna-rp-sma-plug-connector

I also ordered the RP-SMA connector from Cris.

So what jack would I need to order to get these antenna to work?


Your all set if you get the pcb edge mount connector from Cris. Both the antenna and connector are RP-SMA so they match.
 
Finally got my bluetooth module and antenna pigtail so I could finish my LCD. I used some scrap 1" nylon strap and some old plastic buckles I saved from somewhere to make a stylish carrying strap. I used a hot nail to make the holes in the strap and used some aluminum rivets to hold in place. The home sewing machine was plenty big enough to sew the strap loops on the buckles.


2015-01-31 12.31.57.jpg2015-01-31 12.31.46.jpg2015-01-31 12.32.15.jpg
 
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If i can build a wireless launch controller into a ST Communicator ..perhaps its time to see if we can put a LCD receiver into a ST Tricorder prop.

I bought a belt clip for my box but told my friends a neck strap would be better..

Well Done !

Kenny
 
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Our Groundhog Day sale is still going on... ends Feb 5th.

o Eggtimer Flight Computers - $30 (regular $35)
o Eggfinder TX GPS Tracker - $60 (regular $70)
o Eggtimer TRS Flight Computer/GPS Tracker: $74 (regular $90)


o Eggfinder Starter Set (TX & RX): $80
o Eggfinder LCD Starter Set (TX & LCD): $110
o Eggtimer TRS Starter Set (TRS & LCD): $125


Cris Erving
Eggtimer Rocketry
www.eggtimerrocketry.com
 
Here is a quick review of the awesome 3D printed LCD enclosure BLKKROW designed. I want to thank Kyle (BLKKROW) for printing the LCD enclosure for me. It is great design and everything fits in there very well.

3D enclosure


LCD goes in first and I glued the spacers on the LCD


Everything wired ready to go


The momentary and on/off switches fit between the LCD and the RX board, Bluetooth module goes behind the Rx


Lipo fits inside the handle



Handle gets bolted on, back cover is screwed on and it's done!


Size comparison next to the other two cases I have used.
 
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