Another SDR, and this one is interesting...

What have I been saying, ADS/B in and out for under $1000 is possible. There is a guy with an SDR transceiver that will work everywhere 100MHz to 1000Mhz! The Whitebox SDR is being developed and has a smaller following. This SDR has it's own processor on it and can do all the modulation/demodulation on board. The bill of materials for the board is about $300, making retail under $1000 quite possible.

The name is Whitebox as opposed to blackbox because everything about it is known. The more you know the more you can do with it! The source code, schematics and board layouts are on github. Unless you have looked into SDR programming, there may not be much useful there. If you have looked at gnu radio or any of the RTL-SDR programs, this should look quite similar.

The project hasn't changed status in a little over a year, although the author has done several recent interviews on some ham radio podcasts. There was quite a bit of discussion around the 2013 Dayton Hamvention. I believe this device is pretty solid, but I don't have one yet.

Remember that UAT frequency is 978MHz, toward the top end of the limit if this device. It should be no trouble to write the code for a UAT device. The USB out from this board could easily be connected to an external computer, including a tablet.

It will take some software development to finish this project, but with a little bit of work, suddenly there would be a UAT available for under $1000.

Flying Magazine recently published an article about a portable ADS/B in/out device that is under $1500. It may not be under $1000, but it has a chance to be a popular device. The SkyGuart TWX is a portable device that listens on both 1090 and 978MHz and transmits on the 978MHz. It also has GPS receiver and WiFi for connecting to a tablet.

Are we getting close yet?

Android ADS/B in for $20 available NOW!

It is finally available! I predicted it about a year ago, when I first ordered my tablet, and thought about writing it myself, and asked for help. I am glad there are more ambitious people out there, because they get it done. My Android development skills aren't there yet either. I am working on an app that will use maps, but haven't got to that part yet.

The app is $1.50 in the PlayStore, called ADS-B on USB SDR RTL (beta)  it shows up in apps called "USB ADSB..." on the tablet. The USB dongles are really only about $15-20 US, plus shipping. You will probably need an OTG cable or adapter for a phone or tablet. (The OTG cable allows attaching USB client devices like mice and keyboards to a phone or tablet). Really the cost may approach $50 plus a tablet.

The app shows promise, and really looks nice. It starts the map centered on Lakeland Florida, so it needs to be adjusted to where you are. The maps can be sectional, WAC, IFR, and street maps, and can be selected from a menu. The pinch to zoom works, but the menu allows zooming, along with buttons in the upper corners.

When the app comes up, it displays all the available devices, selecting the available device starts the app. The top part shows the map, the bottom part shows a list of the aircraft that the software has heard recently (can be adjusted in startup menu, defaults to 60 seconds).

It appears to be listening for 1090MHz Mode S with Extended Squitter (ES) transponders. 1090ES is the world wide standard. GA in the US will probably focus mostly on the 978MHz UAT devices, since there is more bandwidth available to those devices. See UAT or 1090ES in my other blog).

The developer says it will have weather eventually. Weather alone would make this app worth while, but the aircraft positions is a huge benefit. "Mounting" a tablet in an aircraft isn't hard, and there are a few adapters to make it easy. 

This doesn't completely compete with the Garmin GDL-39, and their Pilot app, but it will give you the chance to see what is possible, and the benefits to having ADS/B service.

I had trouble using it. The SDR dongle is very sensitive to the antenna chosen. I found a link to a site were there are extensive design and testing of antennas especially for ADS-B reception:

http://forum.planefinder.net/threads/ads-b-diy-antenna.23

I chose the simple 1/4 wave dipole and was able to get some reception. I didn't want a large antenna, nor an amplified one. I want to be able to use this portable in rental aircraft and such. It did seem if I got the SDR farther away from the tablet, it worked better. I used a USB extender to do that.

The battery life doesn't seem to be negatively affected running the SDR dongle, the screen still eats most of the battery. Someone suggested a split OTG cable, so it could be connected to power while running the SDR dongle. That is a great idea.

I can't say this will save a life, or replace TCAS for alerting, but it could help someone get the big picture when ATC calls out traffic.

If everyone only does ADS-B in, it looses some of the benefit. The future will require us to use ADS-B out as well, then everyone should be on the same level.

I Ordered a New Tablet.

I wasted a bunch of time shopping on eBay last week. I finally decided it is time to get a mainstream tablet. I mostly want it for work, but think it would be good for doing ADS-B in on the cheap!

I ordered a new Samsung Galaxy Tab 2 10.1. I didn't get the note, it cost too much. The Galaxy Tab 10.1 is still a dual code 1.6GHz device, and ought to be enough power for now, and is less than a year old. It has everything I want; bluetooth, GPS, WiFI and a big screen. I think I'll have to buy an OTG adapter since it uses a proprietary USB connector (just like the iPad).

How can I do ADS-B for under $100 with this? Well, the SDR folks have been working overtime. One guy at least, Martin. He has the RTL2832u dongle talking to the Android devices. It was only a matter of time, since both the Android stuff and the rtl2832 SDR software are all open sourced. It doesn't do ADS-B decoding out of the box, but what the heck, that is only a little more software.

The FAA while  threatening to charge for the charts, still gives them away. It doesn't really matter, for me using old charts on this, since it will probably be just a toy for now. If I were to ever fly with this relying on the tablet for navigation, then I would want the most current charts. If needed, I would pay for them.

I think I could do the development of the ADS-B decoding, and try to use someones mapping software to get the data to display on the screen. If nothing else, decode the TIS-B and FIS-B data.

Yea, I know Garmin and FreeFlight and everyone seems to think anything under $5000 is the a cheap price for ADS-B, but here I am suggesting a $300 tablet, and a $20 receiver it all I need for ADS-B (plus some cables, and software). Imagine if this would run on a $79 Android tablet, then the whole mess is under $100!. That ought to shock those other guys. Sure they are doing it the hard way, separate receivers and all the work to get "certified" ADS-B receivers, but trust me, you don't need to have a receiver "certified".

Since it is GA in the USA, I am convinced the UAT frequencies are the right ones. The FAA will put the same data out on both the 1090MHz ES, and the 974MHz
UAT frequencies. 


Can we make it happen? Want to help? Lets do it!!

Let me know if I forgot something...

Android Christmas

For Christmas, my older son wanted a phone. Without any influence, other than he couldn't have a Galazy Note or an S3, he wanted a Motorola Backflip, or any Galaxy phone. (I think he knew that I wouldn't buy him anything from Apple). We weren't going to pay for an unlimited plan, so I thought it reasonable to get an unlocked phone, and a pay as you go plan. Our older son and daughter went halfs on an unlocked Motorola Backflip. At first I thought this a great idea, but the backflip is so attached to ATT, that we can't load too many useful third party apps on it. I let him use my myTouch 4g until I can get this worked out a little more.

My other son got a JXD S5110 android gaming device. If you have never seen one of these, they are pretty cool. It looks just like an older PSP, with all the same buttons, but without the CD drive in the back. There is a circular Android logo on the back, that makes it look like a PSP. It has a large screen and a ton of software loaded on it (emulators mostly, Mame, N64, GB, etc). It has Ice Cream Sandwich, but you have to load the play store on it.

99% of everything I've loaded on it works. He plays temple run, cut the rope, and NinJump mostly. It has a multitouch resistive screen, and works amazingly well. You have to push, but overall, it impressive how well it works. One thing that doesn't work is Youtube. I can't tell you why.

The JXD X5110 is fragile. He dropped it the first day, and broke the WiFi switch. Why it has a physical switch, I can't tell you, since it is also software controlled. The back comes off of the device easily, so I soldered across the WiFi switch, so we don't have to deal with that. Over the next week, he has dropped it a couple more times, and knocked the power switch loose, and both of the top buttons. The power switch is about the size of a grain of rice, and the left/right buttons are larger push buttons. I was able to re-solder them on. I am guessing they probably flow soldered them with solder paste (RoHS and all). I used plain old 60/40 lead solder and a 15 watt iron. Nothing to it, maybe like 20 minutes total time (it took a little time to find the power button, since it is about the same size as the screws).

I don't know if I mentioned it, but my wife and I both got Galaxy Note 2's a couple weeks before Christmas. That was a good choice, I really like the device, and with the big screen, it makes everything else seem tiny. I haven't done any programming for it yet, but I want to try, especially for the side by side two apps at a time work. I've got podkicker on that, and been listening to the GoogleIO podcasts from last summer. I mostly listen to +All About Android and +Android Central podcasts for insite into future and device considerations. 

I've done a little work to get a development environment setup for the STM Discovery F3 boards I have. I tried really hard to build GNU toolchain from scratch, but eventually gave up and got the Code Sourcery from Mentor Graphics. It is all setup, but havn't built anything to install yet. I am tempted to use the Discovery boards for the processor for the engine monitor, instead of the Arduino. It'd just be nice to move on from 8bitters finally.

I also was working on pinewood derby, and plastic models, and all. Not much time for watching TV, but I want to play with the SDR again. I've kind of let all that go since last summer.

keep in touch. 

Another SDR Post

I started putting together the hardware for the thermocouple amplifiers, but quickly realized I didn't have everything I needed. I needed some reasonable sized capacitors (0.47uf 10V or so) and a trimmer resistor. The closest I could find in my collection was a .10uf at 25V or .33uf at 1000V. I thought, crap, for less than a dollar, I should get what I need. That 1000V cap, while close to what I needed, was bigger than the chip. Board real-estate would be a challenge.  I know it is just a proof of concept, but I needed something better. I have some surface mount caps, but even those were all over the map, like 47uf, or 100pf, nothing kinda medium.

I was thinking a quick order at Mouser or Digi-Key and I would have what I need by Wednesday. Well, it would take a $25 minimum order, and I'd obsess over what else to buy for 5 days, and I wouldn't get what I need until next week. I had a coincidence happen on Tuesday. Traffic was awful, and I needed to try a different way home. I ended up in Farmers Branch. Tanners Electronics is right there. I thought I am close, maybe they stay open until 6pm. IT was about 4:50pm, and I was close, so I thought I'd go for it.

They are open until 6 Monday through Saturday. I could pop in there and get what I needed. When I got there, I was surprised. They had about the same collection of small capacitors as I did, .33uf at 1000V and some surface mount ones. I did find a couple medium ones, one disk, and one film and a small one, mylar I think. I bought an assortment, at least 2 of each, and a couple trimmer pots, spending all of $3, and I had them.

I haven't had time to do anything with them though. I hope to this weekend.

I've been thinking what a full system might look like. How about the Arduino as the engine controller and monitor. This is for the full FADEC system. Then a USB connection to a central hub, maybe an ARM controller running Linux. Another Arduino running DIY Drone air data computer, and IRS gyro package connected to the central controller over USB. Each Arduino would have their own blue tooth connection for sending to the display computers. Display computers would be Android tablets. I am not sure what the central system would do other than data collection. I guess it should share information, with the two Arduino's. Like putting in a TOGA button, the FADEC would run the engine up for takeoff power, then the autopilot would fly the missed approach procedure. The central computer would have some GPS and mapping software, unless that was outboard also (Android tablet may have that?).

Lots of planning and dreaming.

I said this was an SDR post. Well, here is the SDR info. Suddenly SDR hardware is down to about $20! You can buy USB tuner cards for PC's that have untuned front ends for $15-25 on EBay. There is software available to use them, and they are quite popular. They can tune anything from about 64-1700MHz and should work in almost any mode (even TV, since that is what they are designed for!). Reddit has a hardware compatibility chart. 

I ordered one, maybe, I'll have time to play with it. It sounds like it has most of the software written. All I need to do is plug it in and run some code.

I also found the LinuxCNC website. That might be my answer to the 3D printer I've been wanting to work on. Again, when I get some time, I'll take another look at it.