Oinker is Twitter for HAMs

oinker

Have you ever wanted to send a quick message to your HAM radio buddies over the air but then realized you forgot your radio at home? [Troy] created Oinker to remedy this problem. Oinker is a Perl script that turns emails into audio.

The script monitors an email account for new messages and then uses the Festival text-to-speech engine to transform the text into audio. [Troy] runs Oinker on a Raspberry Pi, with the Pi’s audio output plugged directly into an inexpensive ham radio. The radio is then manually tuned to the desired transmit frequency. Whenever Oinker see’s a new email, that message is converted into speech and then output to the transmitter.

The script automatically appends your HAM radio call sign to the end of every message to ensure you stay within FCC regulations. Now whenever [Troy] runs into some bad traffic on the road, he can send a quick SMS to his email address and warn his HAM radio buddies to stay clear of the area.

Listening To A Swarm Of Satellites In Orbit

kicksat

A few months ago, we heard of a Kickstarter with an amazing goal: give everyone with $300 burning a hole in their pocket their very own satellite orbiting Earth. Time passes, the mothership has been launched, and in just a few short hours, over a hundred of these personal femtosatellites will be released into low Earth orbit.

The Kicksat consists of a 3U cubesat that was recently launched aboard the SpaceX CRS-3 mission to the International Space Station. Inside this cubesat are over one hundred satellites called Sprites, loaded up with solar cells, magnetometers, a microcontroller and a radio to communicate with ground stations below. The current mission is a proof of concept, but if everything goes as planned, similar satellites can be deployed into the path of incoming asteroids, or whenever a mission calls for a swarm of small smart devices covering a huge area.

Already the Kicksat mothership has been tracked by a few enterprising amateur radio enthusiasts but the deployment of the Sprites isn’t scheduled until today at 4:00 PM EDT (20:00 GMT). After that, the Sprites will be on their own, spewing out data and the initials of kickstarter backers to most of the population of Earth.

For anyone worrying about these Sprites causing an ablation cascade or a Kessler syndrome, don’t. Orbital decay is a function of surface area and mass, and these extremely lightweight thin rectangles will burn up in the atmosphere in a few week’s time. The lack of radiation hardening on the Sprites won’t be a problem, either. This shouldn’t be a surprise, as they’re orbiting well within our wonderful, protective magnetosphere, and there are digital cameras, tablets, and other much more radiation sensitive electronics that have been working perfectly on the ISS for years now.

You can check out the current location of the orbiting Kicksat mothership on the project website, read the updates on the project blog, or check out our coverage of the Kicksat program from last year’s world maker faire in New York. Relevant videos below.

Oh, and if you have a USB TV tuner, a good antenna, LNA, and some experience with SDR, here’s what you need to listen in.

Continue reading “Listening To A Swarm Of Satellites In Orbit”

Pi-Powered Radio Over IP

Pi

[KP4TR] connected a Raspberry Pi to a small, cheap handheld radio, allowing anyone within a few miles of his house to connect to amateur radio operators all around the world.

For the hardware, [KP4TR] is using a Raspi, a Baofeng BF-888s 400MHz – 470MHz walkie-talkie radio, a USB sound card, and a pair of transformers for the 5V and 3.7V lines. All this is tucked away in a remakably vintage-looking plate and standoff enclosure, complete with acorn nuts and an RGB LED connected to the Raspi’s GPIO to indicate whether the radio is transmitting or receiving.

The software used is SVXLink, a Linux port of the Echolink software. This app allows hams the world over to connect to very distant radios over the Internet.

You can check out the video demos of the system below.

Continue reading “Pi-Powered Radio Over IP”

SSTV beacon based on a Raspberry Pi

The Budapest hackerspace did some joint work with a local ham radio club and created an SSTV beacon housed inside a CCTV case that takes an image of its environment and transmits it using slow-scan television over ham bands.

As the title says, the build uses a Raspberry Pi to process the image taken from its camera and then transmits it over the air using a Ricofunk UHF transceiver with a main frequency of 433.425MHz. On the software side, PySSTV is used to convert images to frequency/time tuples, UNIXSSTV then creates the actual audio file and finally sox plays it. To avoid screwing up the Raspberry SD card, every part of the filsystem is either mounted in read-only mode (things like /home and /usr) or uses a ramdisk (things like /tmp and logs).

The plans, schematics and source code are available, so they hope that other hackerspaces will join the ranks!

Retrotechtacular: Fundamentals of AM and FM Radio Communication

How radios send and receive information can seem magical to the uninformed. For some people, this week’s Retrotechtacular video, “Frequency Modulation – Part 1 Basic Principles”, from the US Army Department of Defense 1964 will be a great refresher, and for others it will be their first introduction into the wonderful world of radio communications.

The stated objective is to teach why FM radio communication reduces interference which normally afflicts AM radio communications. Fundamentals of AM and FM is a better description, however, because the first part of the video nicely teaches the principles of AM and FM radio communications. It isn’t until later in the clip that it delves into interference, advantages of FM modulation, and detailed functioning of FM radio. The delivery is slow at times and admittedly long, yet the pace is perfect for a young ham to follow along with plenty of time to soak in the knowledge. If you’re still on the fence about becoming a ham here’s some words or encouragement.

Though the video isn’t aimed at ham radio users it does address core knowledge needed by amateur radio hobbyists. Amateur radio is full of many exciting communication technologies and you should have a clear understanding of AM and FM communication methodologies before getting on Grandpa’s information super highway. Once you have your ham license (aka ticket) you have privileges to create and test amazing ham related hacks, like [Lior] implementing full programmable control of a Baofeng UV5R ham radio using an Arduino.

Join us after the break to watch the video.

Continue reading “Retrotechtacular: Fundamentals of AM and FM Radio Communication”

Guest Rant: Ham Radio — Hackers’ Paradise

Editor’s Note: This is a guest post written by [Bill Meara]

The suits at Hack-a-Day reached out to SolderSmoke HQ and asked me to send in a few words about why their readers should take a fresh look at ham radio. Here goes:

First, realize that today’s ham radio represents a tremendous opportunity for technical exploration and adventure. How about building a station (and software) that will allow you to communicate by bouncing digital signals off the moon? How about developing a new modulation scheme to send packets not down the fiber optic network, but around the world via the ionosphere, or via ham radio’s fleet of satellites? How about bouncing your packets off the trails left by meteors? This is not your grandfather’s ham radio.

You can meet some amazing people in this hobby: Using a very hacked-together radio station (my antenna was made from scrap lumber and copper refrigerator tubing) I’ve spoken to astronaut hams on space stations. Our “low power, slow signal” group includes a ham named Joe Taylor. Joe is a radio astronomer who won the Nobel Prize for Physics. He’s now putting his software skills to use in the development of below-the-noise receiving systems for ham radio. Join me after the break for more on the topic. Continue reading “Guest Rant: Ham Radio — Hackers’ Paradise”

Turning an easter egg hunt into a fox hunt

fox

We’ve seen [Todd Harrison]’s work a few times before, but he’s never involved his son so throughly before. This past Easter, he thought it would be a good idea for his son and a few of his friends to take part in an easter egg hunt. Being the ham he is, he decided to turn an easter egg hunt into an adventure in radio direction finding, or as amateur radio operators call it, a fox hunt.

[Todd] put together a great tutorial on building a yagi – a simple directional antenna – out of a couple of pieces of PVC pipe and a few aluminum and brass rods. With this and a handheld ham set, [Todd] hid a fox along with a stuffed easter bunny and a basket of candy near a local park. Operating under the guidance of his dad, [Todd]’s son and his friends were eventually able to find the fox. Leaving candy out in the Arizona sun probably wasn’t [Todd]’s best idea – the fox, and candy, were covered in ants when they were found – but it was a great introduction to amateur radio.