My Attempt at a $115 ADS-B Receiver Build for Foreflight

I see this was posted above but in case anybody missed it, the easy days of a low-cost ADS-B solution using the Pi are coming to an end. The Raspberry has been upgraded with a must faster processor, wi-fi and BT built in, and gosh knows what else and of course the price has gone into the stratosphere. It now costs $35!

https://www.raspberrypi.org/blog/raspberry-pi-3-on-sale/

So is it a safe assumption that if we are looking to start this DIY project soon, we should go with this latest version of the Pi?
 
So is it a safe assumption that if we are looking to start this DIY project soon, we should go with this latest version of the Pi?
I would, but check the Github page for compatibility with the on board WiFi:
https://github.com/cyoung/stratux/issues/307

Here is the supported HW:
Use Pi 2
Supported WiFi adapters:

  • Edimax EW-7811Un
Tested RTL-SDR:
  • NooElec NESDR Nano 2 (best)
  • NooElec NESDR Mini 2
  • Generic R820T (degraded performance)
https://github.com/cyoung/stratux

However, I think that future builds will start including the drivers for the built in WiFi (hopefully BT too) by 9b1 or 10b1.
 
Was out flying today and had a few problems.

Traffic would not stay on the screen. Would pop up for a few seconds, then disappear.

Then if I connected to the stratux via safari, it would say disconnected. Refresh, I see the traffic list, go back to fore flight and traffic is shown, then disappears.

Bottom line, it appeared like I kept losing connection to the iPad.

Any idea what is happening?

Cliff
 
Hearing Stratux does not work with the latest version of FF
 
Hearing Stratux does not work with the latest version of FF

While researching my problem from above, im finding the same info.

However, from what I'm seeing, if AHRS is disabled, then everything should work as it used to.

Cliff
 
FF deliberately disabled port 49002 while listening to port 4000 in an effort to cripple Stratux in favor of their proprietary Stratus device.

Quote : "The simultaneous feeding of data to both our operational use and flight simulator use ports was undesirable (unexpected, untested, and not a priority for us to debug, harden, and ultimately support at this time), as was the injection of Stratux AHRS data for operational use. We know what we get at this point with the Stratus 2 and FlightStream AHRS - both Appareo and Garmin have years of experience building certified inertial systems. Lots of time and testing is invested in getting that performance really dialed in, and other priorities are at the top of the stack currently."
 
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That port is just for the AHRS - everything else should still work. Mine did yesterday....
 
What version of Stratux are you running?
 
image.png
Screenshot from the car, no towers - O.6r1 stratux.
 
image.jpeg
Another one just for kicks. Normal ground reception is limited to 50-ish nm on 1079 traffic in the FL28-FL35 range. This hit at 91nm is proof that stratux works, perhaps with too much range...
 
View attachment 44661
Another one just for kicks. Normal ground reception is limited to 50-ish nm on 1079 traffic in the FL28-FL35 range. This hit at 91nm is proof that stratux works, perhaps with too much range...

Update to the most up to date release....I believe its 0.8r1. Should be available on GitHub. That would probably solve your issue.
 
And.... What issue is that? Perhaps I missed something, but I am not having any issues with my stratux.
 
So I got my kit in the mail this week, and just finished putting it together! Right off the bat I am getting traffic on the ipad (FlyQ). Mostly heavy traffic departing DFW.

Two things I noticed if anyone can comment:
1) The GPS appears to be working, my iPad does not have an internal GPS however the blue GPS dot is right over my house and the GPS data on FlyQ says it's current. I thought the minimal kit from Vilros was WX/traffic only, and that I needed additional hardware for the GPS/AHRS functionality??
2) There is no WX data coming through the system... According to the iPad the WX is "days old". Anything I am doing wrong here?

Other than that, this thing is cool. I look forward to customizing the case/setup a bit more so I can take it flying.

Arob
 
Two things I noticed if anyone can comment:
1) The GPS appears to be working, my iPad does not have an internal GPS however the blue GPS dot is right over my house and the GPS data on FlyQ says it's current. I thought the minimal kit from Vilros was WX/traffic only, and that I needed additional hardware for the GPS/AHRS functionality??
2) There is no WX data coming through the system... According to the iPad the WX is "days old". Anything I am doing wrong here?

Not sure about the Vilros kit and the GPS issue, but your item #2 is simple: you can only get weather from a ground station (which is line of sight at ~1GHz), so you'd have to either get up in the air, or drive to a nearby tower to get it to work.
 
And.... What issue is that? Perhaps I missed something, but I am not having any issues with my stratux.
Sorry, quoted wrong post. Was supposed to be targeted at the post that was saying they were experiencing intermittent traffic. Figured it might be the blinking blue light issue with the WiFi adapter.
 
The pi3 is really tidy. I clipped a couple of aquarium suction cups to a 978MHz antenna, then ran an 18" sma to mcx coax down to the nano sdr.
IMG_0229.JPG
 
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So since I'm useless, I'm going to park my butt in here and wait for someone to do all this with raspberry pi 3 and AHRS, then tell me how to do it. kthx.

As an aside, is the pi 3 the same form factor as the pi 2, thus compatible with the cases for the pi 2?
 
Same form factor.
 
Finally got all the parts rounded up to make the Frankenbox. All y'all with your fancy 3D printed boxes...

This one cost a grand total of $8 and there a piece of steel screwed to the lid (thus the two stainless screws - just ones I had on hand in the junk bin in the garage) so the original antennae will "stick" (somewhat well, not great) to the top of the box. (I could fix that problem by cutting a couple more holes so the magnets could touch metal. Maybe I'll go do that.)

15 minutes in the garage with a drill, a jigsaw, some sandpaper, and the box from Amazon. Heh. Cheap, that's me. Doesn't need to be pretty.

578d7de98610d356228a2f428b567174.jpg


68e19640e9788c67db9e38dc9a8e1f2f.jpg
 
Steampunk. Nice!
 
Any concerns about using magnetic mount antennas?
I took the magnets out (using them on the refrigerator door) and put velcro on the bottom. Now I can place them on the glarshield (which is mostly velcro by now) or on a back window ledge (small pieces of sticky-back velcro)

Being in the software/computer industry, I dislike magnets anywhere except on the refrigerator door.
 
Finally got all the parts rounded up to make the Frankenbox. All y'all with your fancy 3D printed boxes...

This one cost a grand total of $8 and there a piece of steel screwed to the lid (thus the two stainless screws - just ones I had on hand in the junk bin in the garage) so the original antennae will "stick" (somewhat well, not great) to the top of the box. (I could fix that problem by cutting a couple more holes so the magnets could touch metal. Maybe I'll go do that.)

15 minutes in the garage with a drill, a jigsaw, some sandpaper, and the box from Amazon. Heh. Cheap, that's me. Doesn't need to be pretty.

578d7de98610d356228a2f428b567174.jpg


68e19640e9788c67db9e38dc9a8e1f2f.jpg


Pictures of how everything is stuffed inside?

What size is the box?
 
This box:

Hammond 1591ESBK ABS Project Box Black https://www.amazon.com/dp/B0002BSRIO/ref=cm_sw_r_cp_awd_yeFaxbRR3SAZY

The 7.5 X 4.3 X 2.2 one.

Couple of these:

StarTech.com 6-Inch USB 3.0 Extension Adapter USB 3.0 Port Saver Cable, Black (USB3EXT6INBK) https://www.amazon.com/dp/B00S2N2Q4U/ref=cm_sw_r_cp_awd_zfFaxbB9HHEVK

They're actually too stiff. Get lighter easier ones to bend, but they'll cost a buck more each unless you wanna go super cheap.

One of these:

[26800mah Huge Capacity + Powerful 5.5A Output] RAVPower Portable Charger 3-Port External Battery Pack with iSmart Technology Power Bank for iPhone, iPad and Samsung Galaxy and More - Black https://www.amazon.com/dp/B012NIQG5E/ref=cm_sw_r_cp_awd_LgFaxbXV141M5

Literally just dropped in the bottom of the box. Highly recommend getting a slightly longer box. As you can see I cut a slot to access the end of the battery and the USB ports. The USB connectors were a little too long to plug in inside the box and all the right angle connectors I could find were also too thick.

Any PI in a cheap case. Cheaper the better. You want it thin.

After the metal strip was screwed to the top, slightly offset so the screws wouldn't hit the PI case, stuck some sticky Velcro on that and on the Pi case. Pi and receivers are side by side and they just barely fit with the receivers turned on edge as you see from the one peeking out of the hole. Receivers aren't velcroed to anything they stay put fine sitting on top of the battery and squished against the Pi.

The power port on the Pi is toward the receivers and that limits them from coming any closer to "you" when looking at the end shot. The receivers bump into it. The flat ribbon cable you see is a USB-A to mini-USB that comes with that battery pack and it works good for powering the Pi.

I just stuffed the antenna cables inside for the shot but I'll probably find a way to wrap them up more after I see if I really want them sitting on the box in the back.

That's about all there is to it. It's kinda a "press fit" just whichever way around it would all fit. Another 1/2" in width and length would make it a little easier but it worked. A smaller or thinner battery would also help to leave some room to stuff cables, etc, but I really like that big battery (I use it for other stuff) a lot. I may get another one. It has three ports for output, a 1.0, 2.1, and 2.4A and a mini-USB for charging. It charges iDevices *really* fast on the 2.4A port. I have a really long USB to idevice cable that I can plug into this battery and run the iPad off of it, at the same time as the Pi. Only warning: The Pi and two receivers will constantly reboot on the 1.0A port. Use the 2.1A or the 2.4A for the Pi.

Whole thing could be prettier and if I could find screws that match the project box thread pitch in a thumb screw design (maybe at Fastenal) I'd replace those so I didn't have to dig out the Leatherman from the flight bag to remove the lid to pop a newer software version in the Pi. But for an experimental box, it'll work fine. (I'd also properly countersink those screws holding the metal plate if I cared to make it "pretty". I figure I'll only be using this thing for a year before something way better is out.)
 
I was thinking more in terms of magnets affecting your airplane's compass.

Oh. It sits in the back seat. No need to have it up front at all. Wifi. Why risk either the RF noise it probably makes or the EM stuff? Just toss it back there. (We don't have any AHRS or other Nav boxes back there either, but if someone does...)
 
So let me ask this, what's the real advantage on having both the 978 and 1090 receivers? I have them both but is it really necessary?
My understanding (I'm no expert): in theory you see more traffic since you can receive the 1090 directly from airplanes whereas you only get the 978 of you happen to be near a plane that is ads/b out to trigger the ground stations to make the broadcast. My observation has been that this doesn't matter because all the 1090 traffic I see is 20K feet above me
 
After the metal strip was screwed to the top, slightly offset so the screws wouldn't hit the PI case, stuck some sticky Velcro on that and on the Pi case


What is the purpose of the metal strip inside the case?
 
What is the purpose of the metal strip inside the case?

Trouble getting going this morning? :D

there a piece of steel screwed to the lid (thus the two stainless screws - just ones I had on hand in the junk bin in the garage) so the original antennae will "stick" (somewhat well, not great) to the top of the box.

Mag-mount antenna.
 
My concern would be with heat dissipation from the pi unit and (more importantly, because they heat up more) the dongle(s).
 
As someone looking to start this project, is there an updated materials purchase list? I read through all 22 pages of this topic and it looks like things have evolved since the original parts list. I just want to make sure I'm buying the latest and greatest to make the project easy. Thanks!
 
http://stratux.me/

That is the "official" site (as much as there is one) and has current parts lists. Including what is now a pre-bundled set on Amazon that comes with the software pre-loaded!
 
I will have some great info for you guys in just a little bit.
 
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