Eggfinder LCD Handheld Receiver and LCD-GPS Module Improvements/Assembly Changes

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H. Craig Miller

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I just received and assembled my Eggfinder LCD Handheld Receiver and LCD-GPS Module, and wanted to pass along some assembly changes that are not yet documented in the instructions. Nice improvements, as a matter of fact.

First, the instructions call for the mounting of two .1 uF ceramic capacitors, but that number has been reduced to a single capacitor.
Capacitor.Compare.jpg
Next, the instructions call for the mounting of a 4-pin right-angle header. There are actually two headers, one 4-pin right-angle header, and a new 3-pin right-angle header for the GPS connection (a fantastic change).

Header.4-Pin.Power.3-Pin.GPS.jpg
The GPS module now also has a matching 3-pin right-angle header for the GPS connection (the other half of a great change), so when the instructions for the module say to cut the connectors off... DO NOT CUT THE CONNECTORS OFF.

Pictures of the changes in the LCD-GPS module assembly will be forthcoming...

I ordered the kit for installation in the Black Aero box, but I am assuming that the electronics are identical regardless of the box used. If you are not sure about what you are getting ready to do (or what you have done), contact Cris before you go any further... the time it takes for an e-mail exchange beats waiting for replacement parts.
 
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The 3-pin header for the GPS module has been on the boards since 2017... when the GPS module add-on was introduced. We didn't reshoot the LCD assembly pictures... I suppose we should.
 
Now for the GPS module assembly... As stated above:

The GPS module now also has a matching 3-pin right-angle header for the GPS connection (the other half of a great change), so when the instructions for the module say to cut the connectors off... DO NOT CUT THE CONNECTORS OFF.

The only other change/problem that I encountered is that the header pins on the GPS module cover the text telling you what the function of each pin is, so, if you don't write down what the pins are before you solder the header pins in place, you will not be able to read the text (ask me how I know). If that happens, remove the black pin separator, and take a picture or write down the pin configuration, then put it back on, and properly orient and install the connector from the LCD module to the GPS module (the wiring on your connector may be a different color than mine).
04.GPS.Header Pins.jpg
If you purchased the Black Aero case, the mounting holes for the GPS module are too large, and must be filled in with epoxy and re drilled, otherwise the screws fall out and could short the circuitry as they roll around inside the case.

A change that I made in the Black Aero installation relates to the on/off switch. The instructions call for the switch to be installed upside down so that the handle screw does not contact the closest terminal. I guess I'm a little OCD because that would bother me to the point I couldn't stand it, so I cut the length of the screw on that side to extend through the nut, but not past the nut retaining tab.
07.GPS.Switch.jpg
Another change I made to the Black Aero box installation was to add charging ports. The receiver battery fits in the handle and, without charging ports, that handle is coming off regularly, maybe several times a weekend depending on how many birds you fly at the event. I installed one connector for the battery terminals and a second connector for the balancing port.
11.GPS.Charge Ports.jpg
And, last, but not least, a protective case for the receiver... and two mini transmitters.
Eggfinder.Receiver.Transmitter.Case.jpg
In closing, as I have said before, if you are not sure about what you are getting ready to do (or what you have done), contact Cris before you go any further... the time it takes for an e-mail exchange beats waiting for replacement parts.

In my opinion, you will not find better customer service anywhere.

Good luck.
 
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Wow, that is an impressive fit and finish on the enclosure!
I am planning to draw up an enclosure from scratch in AutoCad and print it on my Raise3d N2, and make something even more ergonomic. A pistol grip with valleys for fingers, and the display tilted at a natural viewing angel. I'm scheduled to fly my L1 Cert flight on Dec 19th (pending weather, etc). So assuming I end up having the time to design and print it by then, I'll share the STL file.
Brilliant plan on adding an externally exposed charge port, making a note of that.

Regarding the slight changes on the PCB, I wasn't too concerned about the 3 pin header. I was more concerned about the discrepancy on the quantity of caps.

Cris, appreciate the support and engagement here. I think you shipped mine out Monday, and it arrived 2 days later! So now I've got a fun project over Thanksgiving weekend.

I'll share progress here
 
I guess I couldn't leave it alone, OCD and all... so I modified one of my mini transmitters to get rid of some of the extra wire.

Before I started... 01.Rx.Wires.jpg

I began by removing the battery leads and then the diode.
00.01.Rx.Modification.Battery.jpg
After that, I took the center pin out of the new connector, measured the distance between the pins, and marked the circuit board where the hole for the negative connector pin would be drilled (the hole for the positive wire is used for the positive connector pin), then carefully punched the mark so that the bit would not drift while drilling a #60 hole.
00.02.Rx.Modification.Battery.jpg
Soldered a jumper wire (excess resister lead) to the negative connector pin, inserted the pins on the connector through the holes, soldered the positive pin in place, and bent over the negative pin (in between the old diode solder pads) to help hold the connector in place when it is connected and disconnected from the battery, making sure the negative pin did not come into contact with either diode solder pad. Then, properly oriented the diode and soldered it diagonally from the positive connector pin to the leg of the voltage regulator.
00.03.Rx.Modification.Battery.jpg
Plugged in the battery and tested the transmitter to make sure it was still fully functional.
00.04.Rx.Modification.Battery.jpg
Much better... for me at least.
 
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