Sunday, November 29, 2015

My Android ADS-B Setup

This is my Android ADS-B setup. A Droid Maxx running Flight Feeder plugged into an external battery and a USB SDR dongle with an OTG USB cable. The dongle is plugged into a homebrew ADS-B groundplane antenna.

Android ADS-B Setup

The antenna is on top of a 2' length of 1" schedule 40 PVC pipe which is resting on an old microphone stand.

Homebrew ADS-B Antenna

The elements are all 2.67" long. The four angled elements are copper-clad steel welding rods and the center is 0.0625" copper rod. The welding rod was too thick for the center connector and filing the end of the rod down took the copper cladding off and made soldering it in impossible.

The elements are mounted on a SO-239 connector. The screws are long enough to fit into the PVC pipe but I had to cut slots to open the diameter of the pipe slightly. The antenna is held in by the tension of the pipe.

An SMC pigtail is soldered on to the other end of the SO-239 and runs down the inside to plug into the dongle.

Finally, I gave the whole thing a couple of coats of Plasti Dip to make it look cool.

It works. It's a huge improvement over the stock whip that comes with the dongles. The welding rod is stiff but the copper center element bends pretty easily.

Clicking on the photos will open the full-size images on Flickr.

Weird Al and Scripture - Bad Combination

I channeled Weird Al Yankovic and rewrote the lyrics to 'Joy To The World'.

Jeremiah was a prophet
had a lot of ugly news
holy to the Christians
holy to Islam
holy to all the Jews. 
Woe to the world...

Or maybe not.

Happy New Year And Other Random Stuff

Thanksgiving has come and gone. Doesn't seem as cold as it should be this time of year. Global Warming. Sorry, polar bears. Well, not too sorry.

The start of the new liturgical year is today. Ordinary Time has ended and we're now in Advent. A good time to stop and reflect. Like New Year but without the parades, parties, drunk drivers or football games. Yay!

I made a time-and-temperature kiosk display using a television I won in a drawing, a Raspberry Pi and these instructions.  I leave it up when I'm not using the RPi for something else. Pretty straightforward and I'm reasonably pleased with the outcome.

I wonder why time and temperature is so important to me. Maybe I had a thing for the 'time and temperature' lady on the phone when I was little. Or maybe I was deprived. Maybe we were so poor we couldn't afford to find out what time it was and how cold or warm it was.

I snuck a few feet of antenna wire outside to improve shortwave reception. Dramatic improvement.

Speaking of shortwave, I've been hearing a man speaking letters and numbers on 4724 kHz, USB. I recorded an example so you didn't think it was another voice in my head.

If you know what this is, please let me in on the secret. Probably something mundane but I am curious.

In case you're wondering, I was using an Afedri-Net SDR receiver on a Dell laptop with a micro-balun and a random length of wire antenna.

If you've gotten to the point where you've gotten the SDR dongle and upconverter and want to swim out into deeper waters, take a look at the Afedri. It's not cheap and it ships from Israel so repairs could be a PITA. There's no front-end filtering so it's open to everything in the RF spectrum. (Well, there's another wad of cash for a preselector.)

But the guy ships the units ASAP and it seems like a quality build. But best of all, it's a great set of ears. And I've had a few. This is a lot different from the tabletop or portable receivers I've used. Just a whole different vibe. Like going from an all-in-one stereo unit to a component system. Lots of little hassles but lots of flexibility.

I like the metal case of the Afedri and of course the Ethernet connection is dabomb. I can view the entire AM broadcast spectrum at once. And with the laptop I still have the WiFi connection for internet access.

 More later. God bless. And Happy New year! YAY! :)

Saturday, November 14, 2015

I have no idea what these signals are but they sure look interesting. You can click on the image for a larger view.