$30 ADS-B for Android?

RotorDude

RotorDude

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GliderDude
OK, we know that $130 ADS-B can be built with RTL-SDR USB dongle and a Raspberry Pi, connected to a tablet via WiFi.
But we also know that you can connect the RTL-SDR directly (via OTG adapter) to an Android tablet (not sure about iPad) to display 1090 ADS-B traffic (e.g. see this app), e.g. on Avare moving map display.
So what's missing is the FIS-B and 978 side of things, but since we know that works in principle (since it runs on the Pi), shouldn't it also run directly on the Android tablet? (Yes, different environment but not rocket science.)
BTW, I just tried the 1090 traffic on my Nexus 7 with the RTL-SDR and Avare, and I can see traffic just fine.
So is adding the weather to it that hard? Isn't there supposed to be an app for just about anything today?
The Pi is a cute little device, but consider the reduction of clutter and huge simplification if all you had was the RTL-SDR dongle and antenna connected to the tablet.
Comments?

Edit on 10/16/2015: UAT has now been added with FIS-B support and UAT TIS-B traffic (see later posts) but at this point you have to choose between the two bands (restart required).
 
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JoeSelch said:
Interesting question ...

Will poke around some. But my initial thought is, "What about power (for the SDR and tablet)?"
MTA: never mind. I see there is an OTG that accommodates both.


What about this app that claims to do FIS-B as well?
(I don't have an OTG on hand to test it)
https://play.google.com/store/apps/details?id=com.wilsonae.android.usbserial.pro
Click to expand...

Interesting. They seem to have just uploaded the latest release with FIS-B support.
But from what I can tell, everything is very rudimentary, like an alpha version. Still as proof of principle it shows that this approach is feasible, and that the Raspberry Pi in the current low cost ADS-B solution is essentially dead weight, since there is no reason the tablet (Android in this case) can't process the RTL-SDR data directly.
 
So... I now have a new, mini HTPC!
And, a Stratless!
;-)

I like where this is headed...
 
This is absolutely possible. Nobody has written the software to do it on android yet, though. The appeal of beating the Stratus came first.

Sent from my Nexus 9 using Tapatalk
 
mkosmo said:
This is absolutely possible. Nobody has written the software to do it on android yet, though. The appeal of beating the Stratus came first.

Sent from my Nexus 9 using Tapatalk
Click to expand...

Well, there already appears to be (somewhat rudimentary) software to do FIS-B weather and traffic on the Android (see above) by just hooking the antenna and USB dongle to it (via OTG adapter), i.e. no Raspberry Pi.
Presumably, with the right software, the same can be done for iPad and iOS tablets by processing the dongle data directly, without an external Stratus or Stratux, only the dongle and its antenna.
 
RotorDude said:
OK, we know that $130 ADS-B can be built with RTL-SDR USB dongle and a Raspberry Pi, connected to a tablet via WiFi.
But we also know that you can connect the RTL-SDR directly (via OTG adapter) to an Android tablet (not sure about iPad) to display 1090 ADS-B traffic (e.g. see this app), e.g. on Avare moving map display.
So what's missing is the FIS-B and 978 side of things, but since we know that works in principle (since it runs on the Pi), shouldn't it also run directly on the Android tablet? (Yes, different environment but not rocket science.)
BTW, I just tried the 1090 traffic on my Nexus 7 with the RTL-SDR and Avare, and I can see traffic just fine.
So is adding the weather to it that hard? Isn't there supposed to be an app for just about anything today?
The Pi is a cute little device, but consider the reduction of clutter and huge simplification if all you had was the RTL-SDR dongle and antenna connected to the tablet.
Comments?
Click to expand...


Doesn't that sound like more clutter/problem? I'm installing stratux hardwired in my plane to an external antenna and forgetting about it. Futzing around with a tablet connected to a dongle connected to an antenna and keeping the antenna positioned for good signal, and sometimes having it plugged into the power - sounds like a pain. I guess you can get it down from $105 to $30, great, but not worth it for me. You'll also have issues with hardware uniformity - dealing with a million combinations of underpowered, over-spec'd Chinese hardware. Intellectual challenge, maybe. Useful product, not.
 
RotorDude said:
Well, there already appears to be (somewhat rudimentary) software to do FIS-B weather and traffic on the Android (see above) by just hooking the antenna and USB dongle to it (via OTG adapter), i.e. no Raspberry Pi.
Presumably, with the right software, the same can be done for iPad and iOS tablets by processing the dongle data directly, without an external Stratus or Stratux, only the dongle and its antenna.
Click to expand...

Oh, absolutely. I meant something more refined to middleman the data in to one of the EFBs. That's showing somebody parsing it, but if we can't do something more useful with it, what good is it in that presentation?
 
mkosmo said:
Oh, absolutely. I meant something more refined to middleman the data in to one of the EFBs. That's showing somebody parsing it, but if we can't do something more useful with it, what good is it in that presentation?
Click to expand...

I agree. I think what is needed software-wise on both Android and iPad platforms is, as you say, a middleman layer that will process the dongle data and present it to the user's EFB of choice.
 
PA28Flyer said:
Doesn't that sound like more clutter/problem? I'm installing stratux hardwired in my plane to an external antenna and forgetting about it. Futzing around with a tablet connected to a dongle connected to an antenna and keeping the antenna positioned for good signal, and sometimes having it plugged into the power - sounds like a pain. I guess you can get it down from $105 to $30, great, but not worth it for me. You'll also have issues with hardware uniformity - dealing with a million combinations of underpowered, over-spec'd Chinese hardware. Intellectual challenge, maybe. Useful product, not.
Click to expand...

I am not sure what you mean by the underpowered Chinese hardware. If the tablet can process the dongle data directly, all you need is to hook up the tablet to the antenna and power. I do agree that the cost difference is not an issue, but simpler and less cluttered is always better.
Just doing software upgrades by automatically updating an app vs. burning yet another microSD image is a big plus.
 
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https://play.google.com/store/apps/details?id=bs.Avare.ADSB&hl=en

I see that UAT has been added. But at least at this point, it seems you have to choose between UAT and 1090. Still, for weather and GA traffic, this simple $30 Android solution seems cleaner than the $115 one with its additional hardware.
My understanding is that at some point 1090 transmissions will be re-broadcast on UAT also, but I think OUT is needed to make that reliable, and if not in range of a ground station even OUT won't help, so dual band would still be needed for reliable traffic. But I stand to be corrected on this issue.
In any case, I guess I find it hard to see why an Android user would want a single band $115 solution with this one available.
 
RotorDude said:
In any case, I guess I find it hard to see why an Android user would want a single band $115 solution with this one available.
Click to expand...

Correction, Avare user - it's not meant to work with any other applications. There are lots of nice Android EFB apps, but this doesn't work with them.

Also, the USB OTG interface has been known to be fairly inconsistent across different Android tablets. They recommend a specific tablet and the hardware is limited to that. So you're either beta testing your own tablet or using theirs, in which case it's a $75-85 solution not $30.

Stratux is a few bucks more but has a much larger user base, open development, works on every EFB out there (that has ADS-B support) including ForeFlight, allows multiple tablets/devices to connect at the same time, and can be extended to have dual tuners and AHRS.

Plus you can charge your tablet at the same time AND have ADS-B. I've been on long trips and needed to plug in my tablet to keep it running continuously. Having to choose between battery power or ADS-B isn't really worth $30. And when Android runs out of battery, which it will at a fast rate because it's powering the normal tablet functions PLUS a radio tuner, you'll switch to your Android phone? Good luck, you're not beta testing on the fly.

Doesn't seem like an extremely obvious trade-off to me.

EDIT: By the way, if you want to use the proposed ADS-B solution from Zubair Khan (http://zk4u.blogspot.com/2015/10/the-cheapest-and-most-stable-efb-ads-b.html), be aware that this tablet doesn't even have satellite GPS. It says GPS but apparently it's some wonky WiFi based network location code. This is a good example in the differences between the two projects - quality of solution.
 
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PA28Flyer said:
Correction, Avare user - it's not meant to work with any other applications. There are lots of nice Android EFB apps, but this doesn't work with them.

Also, the USB OTG interface has been known to be fairly inconsistent across different Android tablets. They recommend a specific tablet and the hardware is limited to that. So you're either beta testing your own tablet or using theirs, in which case it's a $75-85 solution not $30.

Stratux is a few bucks more but has a much larger user base, open development, works on every EFB out there (that has ADS-B support) including ForeFlight, allows multiple tablets/devices to connect at the same time, and can be extended to have dual tuners and AHRS.

Plus you can charge your tablet at the same time AND have ADS-B. I've been on long trips and needed to plug in my tablet to keep it running continuously. Having to choose between battery power or ADS-B isn't really worth $30. And when Android runs out of battery, which it will at a fast rate because it's powering the normal tablet functions PLUS a radio tuner, you'll switch to your Android phone? Good luck, you're not beta testing on the fly.

Doesn't seem like an extremely obvious trade-off to me.
Click to expand...

I don't have a huge dog in this game, since I am fairly happy with my GDL-39 and Garmin Pilot running on two Nexus 7 2013 tablets. But having said that, I am interested in possible backups (there are never enough) as well as home-brewed things, and a low cost open-source ADSB is very intriguing. I do have a basic Stratux kit running, single band for now, though I haven't tested it in flight.
Anyway, here are some replies to your specific points. As far as being for Avare only, you could be right, but I don't see that as a huge issue. Obviously the greatest issue is that this solution is currently for Android only, i.e. no FF support (although I presume they could broadcast the data on GDL-90, but would lose the single tablet/device advantage, and the price differential would be greater than a Stratux box in any case).
As far as battery power, as I understand it, there are 3 kinds of OTG cables: USB communication with the attached device with no power, USB + power to the attached device only, and USB + power to both the attached device as well as the tablet itself. I have not yet personally experimented with the third type (but have one on order), so I can't swear it works properly, but I do have the first and second type OTGs, and they seem to work as advertised. So even with the second type you at least supply the SDR dongle direct power (in my plane all tablets are fed from the ship's USB outlets, with external and internal batteries as backup).
As far as compatibility with the various types of Android tablets, I have personally tried their latest version (with UAT support) on my two N7s, as well as the G-PAD 7.0 LTE tablet (that AT&T gives as freebie to its phone subscribers). All 3 seem to work fine, and afaik as long as the Android version on a given Android tablet is high enough, odds are it should work.
But again as bottom line, if some Android user prefers the Stratux solution, I see no problems with it. Bear in mind that just as I did, if you are an Android user, you can try both the Stratux as well as the OTG version if you just get the OTG connector, since this solution only requires the OTG and the SDR dongle plus antenna.
 
I've used both their 5 and 100 dollar adsb in on my galaxy tab with avare. I like the 100 dolar solution because I don't look at mymtablet all the time and the exta cables made it clumsy to pick up and put down

5 dollars for the otg since I had the sdr and I got the free app to test
 
I flew with this system yesterday. Specifically with a Nexus 7, Avare, and Avare ADSB Pro version 3, which is supposed to support 978 weather.

KogOiK6.jpg


Sadly, I received no ADSB data. I did double check that I had the 978 option set. This really surprised me, because a week ago I had driven to the nearest ADSB tower with the beta release and did receive data, although no data showed on Avare at that time. On this flight the ADSB receiver showed no data at all.

I was with an instructor working on my CFI ticket, so I didn't have time to troubleshoot anything.

Here are some observations:

1) This was a morning flight on a very clear day, the sun was very bright. In these conditions I can barely see my iPad mini with Foreflight while wearing non-polarized sunglasses. By contrast, the Nexus 7 display was clear and bright! I'm switching to using the Nexus with Flight Plan Pro or Avare at least for these local VFR flights.

2) As written the ADSB receiver will absolutely burn down the Nexus 7 battery. It's written as a notification service, which wants to run all the time. Android gives notification services a very high priority, so the ADSB receiver is going to stay active pretty much as long the device is running.

3) Avare is hard coded to fixed portrait mode. This restriction will be an issue for pilots who prefer landscape mode.

The way the receiver gui works if you select 'auto-restart' then the gui pops up and then disappears on every restart. Not only is this distracting, it's almost impossible to kill once it gets into this state.

Conclusion: This concept is very promising. The ADSB Receiver utility is not yet ready for prime time, but all of the issues I saw are fixable in a straight forward way.

I know the device can receive 978 data, I'm not sure why mine didn't work.

A GTG cable that can charge the device (mine won't charge my N7) is essential.

Once more of the bugs are squashed I can see someone making a dedicated android based device just to run this software. One could certainly undercut the price of competing solutions with it.
 
You can change the orientation on Avare by going to the display settings.
 
RotorDude said:
As far as battery power, as I understand it, there are 3 kinds of OTG cables: USB communication with the attached device with no power, USB + power to the attached device only, and USB + power to both the attached device as well as the tablet itself. I have not yet personally experimented with the third type (but have one on order), so I can't swear it works properly, but I do have the first and second type OTGs, and they seem to work as advertised. So even with the second type you at least supply the SDR dongle direct power (in my plane all tablets are fed from the ship's USB outlets, with external and internal batteries as backup).
Click to expand...

I have now received and tested the USB charger OTG adapter (the third OTG type above), and it seems to work as advertised.
This is the one I got. A bit steep at $17, so if someone finds (and verifies) a better one, let us know.
There are lots of much cheaper ones around, but they don't seem to charge the tablet and power the dongle at the same time, while this one does.
 
RotorDude said:
I have now received and tested the USB charger OTG adapter (the third OTG type above), and it seems to work as advertised.
This is the one I got. A bit steep at $17, so if someone finds (and verifies) a better one, let us know.
There are lots of much cheaper ones around, but they don't seem to charge the tablet and power the dongle at the same time, while this one does.
Click to expand...

Yet another update: I tested the new USB charger OTG adapter on three Android tablets, and at least on one of them it seems quirky, while the non charging one works OK there. So caveat emptor, ymmv, etc.
 
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