OFS Stratux Setup

This is an article describing the initial setup process of an Open Flight Solutions FlightBox Plus ADS-B receiver with the C.Young open source “Stratux” software, for weather and traffic information on Avare 7.8.6 for use in a C-172 with Garmin GTX335 ADS-B Out transponder configured with the ADS-B “In capable” code On. This article will focus on indoor ground initial setup and won’t describe in-flight use or Stratux receiver building and programming, but is likely to provide info useful for initial setup of any Stratux receiver for use with Avare.
NOTES: I may update this article as the installation and testing progresses, likely over a period of a week or more, and even longer if something new is noted later. After reading this article always search our Apps4Av Forum for the latest news, updates, discussion and answers to any questions you may have on this or any topic.

UPDATES 7/2019:
•New versions of Avare no longer require the external Avare External I/O “helper” app to use ADS-B In receivers. The Avare External I/O app should not be installed or used for standard Avare installations and ADS-B, but is still required for some special cases like flight sims and autopilots.
•The Apps4Av Development Team was recently contacted by Sean Chuplis of Crew Dog Electronics, makers of another pre-assembled StratuX receiver. We have not yet reviewed that unit, but it is likely to also be high quality and equally compatible with Avare.

Testing and setup for the following post began Feb.14, 2016 with Avare and its Downloads updated on that date so some aspects may change at a later date. Note that ADS-B In UAT air traffic information is severely limited in aircraft not equipped with ADS-B Out, due to current FAA TIS-B configuration. If you do fly an aircraft with ADS-B Out, to get full UAT traffic you must configure its transponder to send the “ADS-B In capable” code (some installers don’t do this unless you demand it).


ADS-B In is an FAA “Next Gen” aviation product that integrates with their other new products to provide pilots with near real-time air traffic (TIS-B), and much more flight info including graphical weather radar (FIS-B). There are two associated frequency channels: 1090MHz ES air-to-air traffic info, and 978MHz UAT providing TIS-B traffic plus the extensive FIS-B products from a network of FAA ground-to-air stations. Depending on configuration, an inexpensive receiver running the free Stratux software can simultaneously provide both of these free pilot info service channels.

NOTE: There is no reliable FIS-B ground reception in most areas, so initial home setup like this described below typically relies on more ubiquitous TIS-B (traffic data only) from airliners passing overhead for validation. I do get UAT with both TIS-B and FIS-B reception indoors at home, so had the rare good fortune of being able to use that in writing this article.

My understanding is that like Zubair and the Avare dev team, the Stratux (ends with the letter “X”) software was developed with an open source license by Christopher Young and other volunteers as a service to the aviation community. It provides an inexpensive alternative to the popular commercial product with a similar name (ends with the letter “S”). That other more expensive product apparently won’t reliably work with Avare or other aviation EFB/GPS apps aside from one. Since I find Avare to be both simple and powerful, and also completely free of fees and ads; and because I favor both open source software and applying scarce funds to flying rather than expensive toys, I chose StratuX.

FlightBox Plus Description

While it’s possible to build a Stratux receiver for less than half what I paid for the FlightBox Plus, I went with this pre-assembled product. My reasoning is that it’s much more likely to contain quality components, it will probably save me at least a couple of hours researching & building, and comes with some support should I encounter problems. Since the designer and builder (Steve Sokol) has built many of these, probably worked with Stratux software designer C.Young, and it has an FCC tag, I’m also assuming it’s top quality. I paid a little extra for the FlightBox Plus model because even though some of its features may not yet be supported by the Stratux software, like Avare the development and refinement of that app is ongoing and is likely to support the extra features sometime soon. Since I fly VFR with a battery powered $10 ADS-B In receiver aboard, I opted not to buy the FlightBox battery backup. Having heard of problems with Ebay and personally experienced problems with Amazon (e.g. fake reviews or those of a related product from a different supplier or for a different model), I chose the FlightBox from among the options recommended on the Chris Bobbe website.

The receiver arrived quickly via USPS First Class Package mail in a 9.75 x 4.25 x 2.25″ box, with a ship date of 2/7 matching a 2/7 Mfg Date sticker on the receiver inside.

USPS Label On Box

I presume the current Mfg date indicates the latest software and firmware is installed. Box contents included the 5.25 x 2.5 x 1.65″ receiver, two 8″ antennae marked for frequency, a Quick Start Guide and shipping sticker, and a solid little 12-24v cigar lighter dual USB output adapter marked “galaxy-io” “5V-4.8A” and with an aircraft depicted on the shaft. I presume the Chris Bobbe website aircraft logo indicates this adapter is unlikely to interfere with avionics.

Box Contents

The case appears to me more robust and refined than most home-built Stratux receivers I’ve seen, aside from some slight burrs on the inside of the side ventilation slots. If it won’t void the 1 year warranty, I’ll open it up to report on the internals and carefully remove those burrs. Click any of my six slightly distorted (it actually has straight edges) cellphone closeup FlightBox Plus pix below to enlarge it.


I enjoy figuring stuff out, and when I get a new toy it’s common for me to experiment with it. Before reading the Quick Start Guide I assembled it with the excuse of finding out whether that’s easy. It is. Noting that the two identical length antennae have frequency markings at their bases, I screwed them onto the fittings aligned with frequency markings on the FlightBox back label. Note that you need to use the knurled base of each antenna to hand tighten it securely. In terms of physical hardware, the only other step seems to be plugging it into a USB power source.

Antennae Installed

Before powering it up, next I skimmed the paper Quick Start Guide pamphlet. The FlightBox website has a more detailed User Guide and their site also has video tutorials,  though I haven’t yet looked at any. They specify a 2+ Amp USB source and cable, and since I have a cheapo USB power meter I plugged it into my S7 phone’s 2 Amp charger (which for comparison shows about 1.6A when charging my S7 from 15%) and then plugged the FlightBox Plus into that meter. At startup it displayed around 1.5A after a minute or less, at which time the fan very quietly came on (ambient room temp 77F). Inside the case I could see a steady red LED and a blinking green one. On the case top opposite the nearly silent fan three lights eventually all came on – ADS-B: Blue LED, GPS: Red LED, Power: Green LED.

Quick Start (S7 indoors on the ground)

Before connecting with Avare, your Android device needs to communicate via WiFi with the Stratux. To do this, I pulled down the top of the Android screen on my S7 phone, tapped the Settings “gear” icon, chose Wi-Fi, and when “FlightBox-(followed by random numbers)” appeared, I tapped that and selected Auto reconnect, then Connect. I either tap Dismiss when the no internet warning appears, or just ignore it. StratuX of course does not provide an internet connection, only GPS and ADS-B data, so may Android notify you of this.

NOTE: If you try this at home and Android auto-connects to your home network, to switch between them in Android Settings for WiFi just tap the one you want, select Auto reconnect, and tap Connect. Another thing to check after turning WiFi is “Smart Network Switch .” Not all Android devices have that but on my S7 phone, I tapped the three vertical dots at the top-right of the WI-FI settings screen then “Advanced” and it’s the second item in the list and was already OFF as desired. To change that setting, both WiFi and Data need to be on.

Despite being a couple of feet from my strong home WiFi router and with 5-10 other WiFi sources in range, my S7 never switched or lost connection even when I took the phone or Flightbox 30′ or more from the home router.

I tapped the Home button and launched my Firefox web browser, then input on the top address line the “IP” number listed in the Quick Start Guide for the Flightbox Plus. This is the “web address” (URL) for the StratuX that enables you to access its detailed data and settings via your favorite web browser app. I suggest you Bookmark that URL in your Android browser app, since it’s very useful. A web page appeared with extensive FlightBox tech details and live data. I explored the Menu items on that web page, and delighted to see that the Stratux was indeed working quite well. I was even seeing UAT data (weather, etc.) indoors, though ground reception is fairly rare in most of the country. I fiddled with items in the MENU and discovered just how much data the FlightBox was collecting.

FlightBox Status Screen

NOTE: New versions of Avare no longer require the external Avare External I/O “helper” app to use ADS-B In receivers. This functionality is now built into Avare and accessed via the new I/O tab in Avare. The Avare External I/O app should not be installed or used for standard Avare installations and ADS-B, but is still made available for some special cases like flight sims and autopilots.

To connect a StratuX receiver with current versions of Avare, first use Map->Menu->Preferences and select the GPS option, and then External WiFi Port to set the four digit channel code to 4000 (note that your StratuX or other ADS-B In receiver might use a different channel code number). Then go back to the Map screen and scroll the bottom tabs to I/O and read the Help info at the top, then tap the Connect WiFi box at the bottom.

When I first wrote this, using the (now uninstalled) Avare External I/O app, there was an Android setting problem on my S7 phone and in case you don’t see data streaming in the I/O screen I’m including that info here:

As directed in item 9 on this Avare Forum post about Stratux ensure that data is streaming below the ----Output---- line in the Avare I/O app. It wasn't! Even after trying several things was I unable to get my spiffy new Stratux to feed its wealth of data to Avare I/O!

Reading to the end of the above Topic in the Avare Forum, I found this post pointing to a problem with some versions of Android (my S7 phone is running Android 7.0). Namely, that when Power Saving is turned on in Android Settings it may disable "background network usage" such as Avare I/O receiving data from the FlightBox. In Android Settings I selected Battery, and under Power Saving Mode I tapped OFF. I then switched back to the Avare I/O app, thrilled to see that it was now happily displaying a rapid stream of data!

StratuX Connection RECAP:

  1. Your Android device must have WiFi turned on.
  2. Your Android device must be connected to the StratuX WiFi.
  3. Avare Preferences must be set to the correct WiFi channel code.
  4. You must use Avare’s I/O tab to activate the Connect WiFi checkbox.
  5. You must see data streaming in the I/O screen before any ADS-B In (or GPS) data from the StratuX can be used by Avare.

Here’s what I see 7/2019 in the Avare 8.0.7 I/O screen after I tap Connect WiFi (edited to insert data since it scrolled too fast to retain the top Help lines). Note that the WiFi symbol in the Android top bar has an exclamation point (!) correctly indicating no WiFi Internet connection:Next I closed and then re-launched Avare on my s7 phone and when the “Turn On GPS” prompt appeared I tapped No, since Yes would turn on the phone’s internal GPS which would not be used (FlightBox Plus has an excellent WAAS GPS) and thus needlessly consume S7 battery power. In the Map tab of Avare I tapped Menu, Preferences, GPS, GPS Position Source, All Available. Then I tapped Menu, Simulation to toggle it to Navigate mode (otherwise GPS is ignored).

Note: When switching my S7 back to using its built-in multi-band GPS for Avare, I found it didn’t work. After using the Android button for Back (right of the Home key) and selecting Exit in Avare, I tapped the Task Manager button (left of the Home key) and swiped Avare off the screen to Close it. With GPS turned Off in Android, I re-launched Avare and hit the Yes button when it asked “Turn On GPS.” That seemed to activate the GPS in Avare when using the Android GPS setting didn’t. I used the same procedure when switching back to the Stratux as GPS source.


One of the coolest UAT features is NEXRAD weather radar. This is now working in current versions of Avare. Note that in the FAA’s ADS-B standard, weather has a lower priority than traffic so it may take some minutes after connecting Avare to your StratuX before any weather data is available for display. Here’s what I saw after a few minutes 7/2019 on Avare 8.0.7 (note that I’d already set the transparency of NEXRAD in Avare’s preferences so that I can still read the chart through the green radar returns):

When first writing this on a much older Avare version I was seeing slight radar returns on the NWS website with my computer here in the Santa Barbara area, so I was surprised to see none on Avare. I’m including what I wrote then in case it’s helpful for anyone.

I tapped Menu, Display, Select Layer Type, 75 Percent. Then I tapped Menu and the second button in the right column, then under the Select Layer Type tapped NEXRAD. Still nothing, so I checked the FlightBox webpage open in Firefox and tapped its Menu and then Weather options where it said Watching (0) and Recent Reports (10). I tapped on the Recent Reports title and it showed METARS for 10 mostly major airports in the region.

There were large and strong radar returns in AZ on my computer’s NWS radar site, so I zoomed Avare’s map screen out to display all the way to TX but still no sign of radar. It could be that since I’m indoors on the ground receiving only one UAT tower, the NEXRAD data isn’t being received by the FlightBox. It could also be that NEXRAD is only sent to aircraft with ADSB-Out. Another possibility is there’s something amiss with Avare’s display of FlightBox radar. In the web browser display of the FlightBox built-in web page is a line titled UAT Statistics. At that point it showed 2799 below the NEXRAD heading (it was already 1101 in the earlier Firefox screenshot above), so maybe Avare I/O isn’t passing it along to Avare for some reason. I’ll check it again in flight with ADS-B Out active to see if multiple ground stations with solid rain nearby will make a difference.

When I tap Menu and then select METAR from that second button in the right column, it shows a green VFR label on every regional airport with a symbol. Zooming out, it shows MVFR on two San Diego area airports among most others showing VFR. So it seems METAR data is reaching Avare correctly.


The next day I tried out an idea on my S7 phone and it works great. Since the Flightbox can connect with multiple WiFi receivers simultaneously, I plan to fly Avare on my primary tablet and also have it running on a backup S7 phone. Note that work is ongoing to integrate AHRS and other StratuX (and ADS-B In) features into Avare, so some/all of the older info below may no longer be relevant.

I like the PFD feature in Avare but it’s not useful in flight due to the S7 sensor limitations. I was going to dedicate the S7 to the cool AHRS screen in Firefox, but then recalled the S7’s split screen capability. Check this out.

AHRS Split Screen

Avare needs to be the active window, but the AHRS in Firefox is active and accurate. At the same time, Avare is showing traffic and METARS (green VFR tag) for my input IZA Destination. It also works in Landscape orientation (see sample at the Apps4Av Forum link below), and I can change the relative screen sizes and zoom the AHRS screen in Firefox if desired to see more of it (like the skid indicator at the top). Tho I fly VFR this will be a great backup to my old “steam” turn/bank and Attitude Indicator instruments. I might get more of Avare’s top Status items to show by reducing the Android font size.

That’s it for now. Overall I’m very pleased with the purchase, and happy to have solved a few setup problems. I hope the solutions I’ve found may be useful for others using Stratux with Avare. Next I’ll take it flying and post Forum articles about that. At some point I hope to also create a how-to video to post on the Apps4Av YouTube Channel. I welcome your comments, questions and feedback in the Apps4Av Forum.

Posted in Avare, Other apps, Uncategorized

New +Apps for Everyone

Starting in 2018 Apps4Av is releasing new Android apps useful for anyone but not specifically designed for aviators, in the new +Apps section. To learn more, Click here.

Posted in Other apps

New Avare Videos

We’ve just published two new Avare Intro videos on our new YouTube Channel, Avare and more, by Apps4Av.

These videos are designed to be fast-paced with many details provided in a short time, so that you can pause or back up and repeat any parts you’d like to understand more fully. The two videos are:

Avare Intro – Part 1: Installation – a brief tutorial on how to install and perform initial setup of Avare, so as to start using it more quickly.

Avare Intro – Part 2: Preferences & Features – builds on Part 1 with a tour through some settings in Preferences that lay the groundwork for getting started with Avare basics. Then it takes you on a quick tour of some commonly used features.

After watching these two videos, our hope is that you’ll find it easier to get comfortable with the Avare user interface (as of version 7.6.8). This may help you to continue exploration on your own with a basic understanding of the core features. Because the app has so many powerful features, each user tends to fine-tune their specific setup and focus on specific functions over time.

Please consider sharing your comments on these videos or your uses of Avare or our other apps on our Forum. We may post more videos, and revise or replace these as the apps continue to evolve.

Posted in Avare

Avare 7.2.3 – 3D Option

Avare version 7.2.3 has added a new “virtual reality” 3D view option! Now you can tap the new “3D” tab to view selected chart types (currently intended for Sectionals and IFR charts, with more to possibly be added). In the new 3D view, these charts show ADSB traffic, terrain, and obstructions in the vicinity.

For comparison, here’s a cropped screen capture from a Samsung S4 phone (with GPS Off in Simulation mode) showing the LA Sectional in the familiar basic Map view:

KBUR Map View

KBUR Map View

There may be occasions in flight planning, in flight, to spot ADSB-In traffic, inadvertent flight into IMC, or other situations when it could be helpful to tap the new “3D” tab to get a view like this:

Avare v7.2.3 Sat View

Avare v7.2.3 Sat View

This places Avare in “Satellite” view mode as if seen from high altitude, with the chart “stretched” over terrain. ADSB-In traffic and obstructions would also be shown in 3D if those options are active. Returning to Map view is done with a tap on the Map tab button. To see the same area in the 3D “Pilot” view, just long-press the “target” Center button at the bottom of the screen to see something like this:

Avare v7.2.3 Pilot View

Avare v7.2.3 Pilot View

Note that the Center button turns green to indicate your view mode, and you can long-press it again for a return to Satellite view or tap the Map tab for that view. As you can see, this mode could be helpful for a quick glance (especially on a backup Avare device like a phone) in IMC or a night approach, and will be much more intuitive in motion than in these static screen capture samples.

Another view option now available is “Shaded Relief” if you Download the file for your area in the Terrain section (Shaded Relief SW for my area of SoCA). This gives you more apparent 3D terrain detail without the aviation chart markings. Here are two edited S4 phone KSBA screen capture samples:

KSBA Shaded Relief Sat. View

KSBA Shaded Relief Sat. View

KSBA Shaded Relief Pilot View

KSBA Shaded Relief Pilot View

See the Help info built into Avare for details on how to use this new 3D feature, and watch for further refinements and additions in future version updates.

Note: You will need to update your elevation file after launching this new version in Map view using Download->Terrain, and you’ll also want to ensure that you have the latest version of the charts you use.

As with all aspects of Avare and the other Apps4Av products, we welcome your feedback and questions in the open and free Apps4Av Forum.

Posted in Avare

Flying Avare In Canada?

We are investigating the potential for adding more capabilities for flying Avare in Canada. It would be helpful if anyone interested in this topic would post a message on our Forum, so we can gauge how many of our users fly Avare in Canada and would like to see more capabilities added. Also what specific capabilities might be most useful.

Clearly, having official Canadian charts and data would be very popular and helpful, but to date we have been unable to obtain free materials of that kind.

To fly Avare in Canada as of this writing (October 8, 2014), be sure you go to Map, Options, Preferences, Display, and turn on Show All Bases. That enables you to Find any Canadian destination that’s in Avare’s database and fly GPS direct even without any map displayed. To display a Canadian map, in the Download menu near the bottom is a category currently named “Topographic Maps(42)” which currently only contains Canada Grid maps numbered 1-114. To find out which grid map(s) you need for the area you fly, consult this UNBC key map. Note that because this link was changed by UNBC recently, the key map linked to from Avare’s in-app Help stopped working and that will be fixed in the next Avare release. Meanwhile, here’s a small version you may find helpful.

Editied canada_grid map

Editied canada_grid map

Click the map to see a larger version, and the original largest and complete version is available on the UNBC map link above. Note that the grids are numbered vertically in rows from East to West and South to North. If you find a better grid map online, please post about it in our Forum.

In the current version of Avare, you might encounter some difficulty in switching between U.S. charts and Canadian Topo. If so, it might help to use Simulation mode if your current position is not in Canada. If that doesn’t help you might also Exit and restart Avare. We very much want to improve and add more Canadian capabilities in Avare, but receive very little feedback and few inquiries. If you fly Avare in Canada or would like to, please contact us on our Forum.

Posted in Uncategorized

Free Geo-Referenced IFR Plates in Avare

You can now install free “Geo-Referenced” live IFR Plates in Avare, thanks to the volunteer work of a “tagging” team that manually added and checked Geo-reference data for almost every FAA Plate. This means that Avare can now show your actual position on the Plate during an IFR approach, updated in real time while on the active area of the Plate, similar to how your position is shown during taxi on the Airport Diagram. These free Plates are a great way to add situational awareness in flight, even for VFR flying.

Steps to install & activate live Plates:
1. Ensure that you have Avare version 5.7.7 or later installed.

2. Download the “Plates Geo-reference Info” file, using:
Options > Download > Plates/d-TPP/ADs

3. Install all of the area or state Plates desired, using:
Options > Download > Plates/d-TPP/ADs

4. Use the Plate button at the bottom of the screen to bring up the Plate menu, and select the desired plate.

A Green dot  over the runway on a Plate is an indicator that it has been Geo-referenced, initially checked, and is ready to use for your further verification and situational awareness.

Note that like all apps on handheld devices like phones and tablets, Avare is not FAA Certified and can not be used for primary navigation in either IFR or VFR flight. As with all such apps, Avare may be used as an Electronic Flight Bag for informational purposes and as a tool for secondary situational awareness.

If you have questions or tips on using Plates in Avare, please share them in the Avare Forum.

Posted in Uncategorized

$10 ADS-B Receiver for Avare

For anyone interested in the smallest possible investment to get ADS-B on Avare, here’s my report on using a $10 “SDR” receiver with the free open source version of the ADS-B app by HIZ:

With a very small investment of time and money, you can now display 1090ES ADS-B air traffic (TIS-B) on Avare. There’s a good chance that we’ll soon see all available ADS-B data displayed on Avare in this way. This will probably work with most Android devices, though the process might vary on some devices. From what I’ve seen online, it’s likely that with a good quality OTG cable (about $7) and a good SDR (about $8) nearly anyone can have it working within a few minutes. Many people report success with the cheapest SDR & OTG available for well under $10 total. If you have no idea what an OTG or SDR is, no worries – I’ll provide a brief explanation and links to details on some terminology below.

As you know, most ADS-B receivers cost somewhere in the range of $1,000 and many of them work great in Avare. Now for about 1% of that investment you can get some of that capability using a small USB stick with an antenna and a short USB adapter cable called an OTG (“On The Go” – a silly and pretty much meaningless name for an item that lets you plug more types of USB devices into many Android devices).

The small USB stick is a receiver that works startlingly well and is called an SDR (aka RTL2832U or most relevant to this app: RTL-SDR). Basically it’s a very capable mass-produced USB broadband receiver originally designed for Digital TV in Europe that can be re-purposed via software to do thousands of other cool things, like ADS-B.

Both the OTG and SDR have been available since Avare was introduced, but until now nobody had created the app to make it all work with Avare. The upside is that it’s amazingly cheap and easy. The downside is that right now unlike some of the expensive aviation receivers it’s only providing Avare with 1090MHz traffic (TIS-B) data (basically, airliners). Not yet very useful for GA, but if enough pilots are interested now the chances are quite good that full 978MHz ADS-B In UAT capability could be included within a few months. Currently it only provides 1090ES band reception for ADS-B Out international, Mode C & Mode S aircraft transmitting air to air. This does mean however, that most people can use it on the ground (often 978MHz data is only available in flight).

Hardware Tested For This Review
Device: Nexus 7 (1st Gen) running Android: 4.4.2
OTG Cable: $6.42 StarTech 5″ (much cheaper cables are available)

OTG Cable

OTG Cable

SDR: $8.86 Jummax

SDR Example

SDR Example

Notes: My impression from reviews online is that the most likely problem with getting an SDR to work is a defective OTG cable, so I bought this “expensive” one. If you have trouble, trying a known good OTG cable would be a good place to start. The CD wasn’t included in the SDR as pictured, but neither that nor the remote control unit are needed for anything but European TV anyway. The included antenna worked surprisingly well, and there are articles online about how to improve it or make your own. I saw several variations on this SDR hardware that look identical, though some show the outline shape of the black USB stick rounded at either the same or opposite top & bottom end corners – this is probably because you can insert the USB plug cap either way. Many reviews say the ones that look like this work fine, and recommend getting the cheapest one from a well-reviewed supplier.

Apps Tested For This Review
Avare: 5.6.7
Avare I/O: 2.0.8
ADS-B SDR app: 1.4.4

Test Location
Indoors, about 4 miles East of SBA and 4 miles South of the commercial air traffic route over RZS VOR.

Testing Process
1. Assemble and plug in the SDR antenna, plug the OTG cable into the SDR and then into the Nexus 7.
2. Launch the ADS-B app.

ADSB app Main Screen

ADS-B app Main Screen

It immediately showed “Packages” being received (note that these screen captures are cropped to save space). The “Bad CRC” line basically shows the signal quality, outdoors or aloft with a better antenna the percentage would be lower, and “Bad” data is automatically rejected by the app.  After a few seconds I tapped the Data button and saw an ICAO number, speed and heading in what is apparently called a “Frame” (paragraph).

ADSB app Data Screen

ADS-B app Data Screen

3. Launch the Avare I/O app, tap the WIFI button and the Listen (43211) checkbox.

Avare IO app

Avare IO app

Though we’re using the WiFi section in this app the actual connection is via USB and no WiFi is available from the SDR, so WiFi on the Nexus 7 (or other Android device running Avare) is not needed. You can leave the Android device WiFi off and in “airplane mode” to save battery.

4. Launch the Avare app, tap the Options button, then the Preferences, Display, and Show ADS-B Traffic buttons, and return to the Map display.

Avare with ADSB Traffic

Avare with ADS-B Traffic

Air Traffic is shown as a jet icon at the bottom-right, beneath the small gray rectangle containing 36025′ in white text. Because no other traffic is close to this jet transmitting ADS-B Out, GA traffic much lower at those coordinates is unlikely to show up because few have ADS-B Out.

About These Screen Captures
These were taken within perhaps a minute of each other as I switched screens, and I’ve cropped them to save space. I think the Avare target shown next to KWANG intersection bottom-right at 36k’ was out of the LA area northbound.

*The antenna supplied with the SDR is designed for European TV reception, and is almost certainly not the correct length for either of the ADS-B frequencies.  So I was surprised that it works at all, especially indoors. One trick I saw in an Amazon review is sticking the magnet base of the antenna to a small ~2″ diameter tin can, and that might be a quick way to reduce the “Bad CRC” number to get quicker & smoother target tracking.

*Commercial traffic within about a 35nm radius was displayed. There are mountains in the SBA vicinity that might be blocking transmissions, so longer ranges with more targets might be seen aloft or on flat terrain and of course with a better antenna.

*Battery use was fairly high.  In this brief (perhaps 45 minutes) test about 15% of battery capacity (from 65% at start down to 50% at end) was used.  The SDR gets warm, so it’s using considerable battery power.  An external powered USB hub to supply the SDR (and ideally also the N7) might be prudent for most flights. If you have or buy such a hub that works well for providing power to both the SDR and your Android device while also passing the data between them (i.e. it works), please post the hub’s make and model to the Apps4Av Forum. The Nexus 7 used 15% percent of its battery capacity during this 45 minute test.  Since I fly with screen brightness at 100% that’s what I used for this testing.  Afterward I closed all apps and left the SDR plugged in (and warm), and with screen still on and full brightness it took four minutes for battery percentage to drop from 45-44% which was much less battery use than I’d anticipated.  It would surely be different on a phone or other device that doesn’t have the beefy battery in the Nexus 7, but you’d get better results with the screen turned down or off when not needed in flight.

*UPDATE: I tried this same SDR on my Samsung Galaxy S4 phone (at home as above), and it was showing these two targets within a minute.



The battery went from 89% to 86% in the 5 minutes it took me to do the test, again with screen at full brightness. Looks like this could work on battery long enough to be useful in flight, at least as backup.

*The app’s current 1090MHz frequency is only showing a very small portion of traffic (ADS-B Out), nearly all of it commercial jets. It is also not currently showing all the other UAT services provided by the FAA on the 978MHz frequency (weather, TFRs, etc.), though that could be added.  You can find a concise and mercifully brief summary of ADS-B in this recent AOPA article and this more extensive FAA FAQ.

*The app is also less useful right now unless you pay for the “pro” version since the free version times out and requires a Restart.  Then it takes a while to re-acquire enough data to reliably show this limited traffic on Avare.  In actual flight for most situations you’d do far better (and be much safer) to just look outside and ask ATC for flight following. If all the UAT data isn’t soon provided to Avare by this new app, other SDR apps will probably be adapted to feed the entire UAT data stream to Avare making the $10 hardware investment much more useful.

But … for this very small investment of time and money right now you will have a portable ADS-B that shows commercial traffic. Very cool toy to show other pilots, play with at home or on a walk, and when you’re flying in busy airspace: to pre-spot the heavies and impress ATC. When I transition LA airspace to MYF, now I’ll know in advance when there’s an airliner inbound for LAX or BUR and plan accordingly. If you ever fly in congested airspace, you’ll also see a lot more traffic because those jets with ADS-B Out will illuminate all detected traffic in their vicinity. When you finally have ADS-B Out in your aircraft, you’ll already have everything you need to display all identified traffic in your vicinity and you’ll be familiar with using it. You’ll also be encouraging Mike and the other developers to expand and improve the ADS-B options for Avare.

It’s really exciting to see any ADS-B traffic for an investment in the range of $8-15 and ten minutes to install and set up.  The app is quite easy to install and use, because Avare automatically displays any detected traffic right on the current chart.

It’s truly Wonderful that this SDR ADS-B app is open source.  That fact seems sure to greatly expand the free and low cost ADS-B options for Android devices going forward.  Thank you, Mike Hammer of HIZ LLC and the Avare development team!

Once the other ADS-B data channel has been added to an SDR app, because Avare already supports it, anyone who has this cheap hardware in an aircraft with an ADS-B Out transponder will get all of the ADS-B weather, traffic and other data now available. This means aircraft can be equipped with the least expensive ADS-B Out transponder available, rather than those linked to a complex and expensive panel receiver/display. It also means pilots who rent ADS-B Out aircraft won’t need to learn and use those complex panel units to get all the benefits of ADS-B on Avare. Just hook up the simple and powerful Android device & SDR you carry in a pocket of your flight bag, and take off.

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