Portable ADS-B in with good AHRS

aterry1067

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Alpha_Delta_Tango
I didn’t want to hijack other sentry, stratus, GDL threads, so decided to start a new one.

I currently have a Stratux for ads-b in. It works great for ForeFlight and ads-b in, but the ahrs goes full spinny as soon as the aircraft moves. I completely understand that a portable unit cannot be relied upon for ifr flight, and that is NOT what I am asking. Please save the self-righteous multi-10k dollar latest Garmin panel humble brag for another thread; I’m not interested. What I am asking is, ForeFlight offers ahrs on their app, and I’d like to play with it. But with the stratux, it’s worthless. So, is there an adsb-in unit that has a somewhat stable ahrs that can be used in ForeFlight? Do you have personal experience with that unit?

Any personal experience response is appreciated. Thanks.
 
I have GDL39-3D units hard wired in both planes. If I use my GP screen on the iPad with the GDL, I can’t see any difference between it and the G3X. I’m happy.
 
I currently have a Stratux for ads-b in. It works great for ForeFlight and ads-b in, but the ahrs goes full spinny as soon as the aircraft moves.
Maybe you got a bad AHRS chip. Mine doesn’t do that and it should be about $20 to replace. And did you go through the aiming before mounting?
 
I think self-righteousness over having a backup AHRS ended about a week after Foreflight added synthetic vision almost 10 years ago.

I tend to agree with @masloki's analysis. But if you want to go commercial product for portable ADS-B with AHRS, just about any compatible one will do. The Foreflight/Sentry, Stratus, and Garmin offerings are the most popular. But even a used Dual XGPS 190 will do the trick.
 
My Stratux AHRS has been rock solid for 4+ years, as have the other half dozen I assembled. Check the module.
 
Been flying with a Sentry for a few years. The AHRS has always worked, but has just enough delay that it's fairly difficult (for me) to fly the plane by that reference alone. I've tried many times practicing under the hood, during IPC flights and even just VFR. I seem to to do much better with partial panel. Probably because I'm old school and still fly steam gauges.

However, I just upgraded the Sentry firmware and it seems to have addressed an issue that was giving me problems before. Previously, when in level flight, the indicated horizon was not on the line between blue and green/red, but a yellow line above what I would've called the horizon. It always looked like I was flying in a nose high attitude when in level flight. Now, I just fired up the new firmware as I was typing this and it now shows the horizon right where I think it should be....ON the horizon. I'm going to try it out on my next flight. Maybe the latency has been addressed also. I'll post about that too.
 

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There’s a problem with your device, not Stratux in general. I used a Stratux for years while I was renting and AHRS always worked fine.

Did you build your own Stratux? Time for a little troubleshooting. You may have a bad AHRS part, but first check carefully for damage, FOD, a bad solder joint, etc.

You might also try re-flashing the SD before doing anything more invasive; that sometimes solves a multitude of problems. The Stratux does not do an orderly shutdown if you remove power without first commanding it off, and that can corrupt the SD.
 
The Stratux does not do an orderly shutdown if you remove power without first commanding it off, and that can corrupt the SD.
If you have upgraded to the latest b3nn0 builds, the base pi image is read-only and logging is turned-off so corruption due to power removal is negated. SD cards still can degrade without any outside assistance though. But, corrupted cards are a lot less likely now.
 
I’ve owned a Stratux, a Stratus, and a Sentry. The Stratus blew the other two away when it came to AHRS (and really blows the Stratux away in adsb reception). As mentioned above by @Lon Stratton the Sentry has a lag, and I never found the Stratux reliable. I would have no qualms about using the Stratus as a back up, it works really well.
 
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Thanks all. I have recalibrated the unit, re-flashed the sd, and also reloaded the software multiple times. I completely agree that it’s a problem with my stratux and ahrs chip. My question came mainly from troubleshooting and reading reports from others. From what I had read, the ahrs chip is very close to the cooling fan, and the vibrations from the fan cause the ahrs to drift. That appears to be what’s happening with mine. It seems like it’s steady enough when stationary, but as soon as I start moving around or as soon as I start the airplane, the vibrations will cause the artificial horizon to start turning right and it doesn’t stop. I may try another ahrs chip, and possibly a new fan to attempt to reduce vibrations. But from what I read on stratux specific forums, it may be a fools errand. Fixing this unit would certainly be cheaper, though. Other than the ahrs, I’m very happy with it.
 
If you have upgraded to the latest b3nn0 builds, the base pi image is read-only and logging is turned-off so corruption due to power removal is negated. SD cards still can degrade without any outside assistance though. But, corrupted cards are a lot less likely now.


Good to know. Thanks. I haven't updated mine in several years; my Beech has a Stratus, so the Stratux just sits in a bag.
 
How do you "command off" a stratux? I've just been pulling the power.

With the tablet that's connected via wifi to the Stratux, open your web browser and type 192.168.10.1 into the address bar. That will take you to the Stratux status page. Go to "Settings" (left side of screen, last item) and select "Shutdown" (mid-screen).

BTW, that status page is where you re-set the AHRS, and you can see status of ADSB towers, see a listing of reported traffic, and other neato things.
 
With the tablet that's connected via wifi to the Stratux, open your web browser and type 192.168.10.1 into the address bar. That will take you to the Stratux status page. Go to "Settings" (left side of screen, last item) and select "Shutdown" (mid-screen).

BTW, that status page is where you re-set the AHRS, and you can see status of ADSB towers, see a listing of reported traffic, and other neato things.
Yep, found it, thanks. Long with opening it, wiggling connections, trying a new cord and power source, seems to be working better. After the wiggling, new power cord, correct shutdown, was working much better, showing traffic in the ap settings map. Nothing showing up outside on the Ipad, though, and I'm assuming the "no towers" is because I'm sitting on the ground.
 
Yep, found it, thanks. Long with opening it, wiggling connections, trying a new cord and power source, seems to be working better. After the wiggling, new power cord, correct shutdown, was working much better, showing traffic in the ap settings map. Nothing showing up outside on the Ipad, though, and I'm assuming the "no towers" is because I'm sitting on the ground.

Yeah, it's hard to get data from the towers when you're on the ground unless you're in a wide open area and near a tower. If you have some traffic filters set on your EFB (like not displaying anything 2000' above your altitude), that would explain why you're not seeing planes even though the app settings map shows them.
 
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