Update: I have an updated RAM Stratux case.
This is my take at a Stratux case remix. I wanted something better than the plastic injection case sold on Amazon (https://amzn.to/2VFRRFG). My goals are: to shorten overall height, have it easy to mount and unmount (portability), and to improve and make consistent GPS accuracy.
I like to mount on the left rear seat window on the C172. The plastic injection molded case with the antennas were too tall. I also wanted a no-fuss mounting solution. Since I rent, it needs to be easy-on, easy-off.
Going to test to see how this set up compares with the injection molded case set up with an in-flight test. If I still don't get accuracy I want, might just go back to the external GPS and figure out another mounting solution.
I had printed mistertech's Stratux case earlier and assembled my Stratux with a GPYes (https://amzn.to/2Wf6Aob). I experienced GPS accuracy and reception issues with the internal GPYes unit like many other Stratux users have also experienced.
Later, I found Kevintjuh's GPS shield design and printed just the shield portion to see if it would improve the horrible accuracy (30M as measured by Foreflight). But it did not fit in mistertech's original case so here we are with a freshly designed GPS shield.
- Bottom of case is no change from mistertech's design.
- Top of case is modified to include a fan mount similar to the popular Stratux box. (https://amzn.to/2XTkAob) No screws, just two built-in clips.
- Top of case is also modified to have an inset for the screw head that will allow me to mount the entire enclosure to a suction mount I have already purchased previously for Stratux. (https://amzn.to/2VHQWF6)
- GPS Shield is inspired by Kevintjuh's shield design. But I wasn't able to remix it or make it work/fit so I made a new one from scratch. Used CyberCyclist's RJ-45 cap and flintol's USB Cap to mount the shield so it's not just floating around in the case. A few prints for the scrapper before I got the alignment right.
The shield should be snug to the GPYes unit. The bottom of the GPYes unit has a metal casing that is already connected to ground on the Raspberry Pi. (Tested with a multimeter) When you wrap the shield in double-side conductive copper tape (https://amzn.to/2ZO2RA4), make sure it has good contact to the bottom side of that casing! Doesn't hurt to test again after mounting with a multimeter.
Control: Tested with the Stratux plastic injected molded case. GPYes antenna side facing directly up clear view of the sky, 30m accuracy on ForeFlight. Same accuracy indication when oriented vertically, as if mounted onto a C172 window.
Test: Tested with this setup with conductive GPS Shield grounded to the Raspberry Pi. GPYes antenna side facing directly up clear view of the sky, 3m accuracy on ForeFlight. When oriented vertically, 10m accuracy.
Will test to see if improvements exist in track log while in-flight.
Everything is pretty straightforward except:
- If you have the pigtail cables that go with the antennas, you'll need to arrange them in such a way that it'll fit snugly before you finish tightening the end onto the case. Mine had an L shape end and I had to ensure each pigtail cable can make one complete loop while still being able to connect to the SDRs. They came as a set, I got the NooElec's and took the plastic casing off (https://amzn.to/2GSBlJ4).
- The shield will fit snugly as designed. It will take some finesse to get the GPS Shield + Pi combo into the case without breaking anything. TAKE THE SD CARD OUT BEFORE ASSEMBLY. That will give you a few more millimeters on one side to push it in under the screw mounts on the wider end of the case and prevent you from damaging it.