AmateurRadio.com

I’ve been reading about the AMSAT Fox Project, an initiative to deploy small next-generation “cubesats”. The website includes several PowerPoint presentations on the design, testing, and engineering of these birds. A lot of work goes into building a satellite, and the number of considerations is just mind-boggling, with concerns about heat, materials, radiation, and resiliency to failures to name a few. This really is “rocket science.”

I’ve been thinking about a more down-to-Earth project for guys like me who aren’t rocket scientists but are intrigued with little devices like these. I’m not sure what to call this yet (perhaps “CubeCache” or “RadioCache”?), but the idea combines geocaching, fox hunting, beacons, microcontrollers, and a touch of repeaters all in one bundle. Imagine if you could build a tiny device similar to a cubesat and place it somewhere stealthy and have it act like a multi-purpose beacon, a simplex repeater, a fox transmitter, and a data gathering on-the-air geocache. The little box would have a small self-contained battery and be equipped with solar cells for charging them. A microcontroller would control all functions of the unit. During low battery times, the microcontroller would put the unit in power-saving sleep mode, turning off all modules. The unit would have a transmitter and receiver, and a second receiver for telecommand functions to comply with FCC rules.

The unit would have several modes. It would announce itself like a beacon periodically. It would act as a “radio geocache” and would receive digital callsign messages and acknowledge them, storing them in memory for later retrieval. The unit could also act like a real geocache, but with a twist. Users could activate fox mode and radio direction find their way to the unit.

Building such a unit would present some technical challenges. The first would be stuffing everything into a small, weatherproof package that can withstand the elements. Much like geocaches, the unit would have to be stealthy both in construction and placement to avoid being found by “muggles”, the geocaching term for people who are not geocachers.  Power management is another challenge, with the need to keep track of battery capacity and make the best use of power. With an experimental project like this, it’s likely the microcontroller software would be changing quite frequently to improve performance and add new features, so a remote over-the-air firmware uploader and bootloader would be helpful.

I’m sure some will ask what the point would be of building such a contraption. Much like a lot of what we do in amateur radio, there often isn’t much of a point other than to experiment, learn, and have some fun. I may explore this idea further in 2012 and build a very simple prototype, place it in my backyard and see where this project goes.  If anyone is interested in helping develop this idea, please let me know.

First, the obligatory “my apologies for the lack of posts recently” statement.  The usual excuses apply: work, family, sleep, more work, and my forty-something mind and body just doesn’t seem to have the get-up-and-go like it used to sometimes.  But I digress.  While I have the floor here, let me take a moment to wish everyone Happy Thanksgiving!

On the topic of radio, Oscar, DJ0MY, has created a professional quality keyer using the Arduino Nano module and my open source keyer code.  Here’s a video of Oscar’s creation:

Oscar has been a big help in suggesting and testing features of the keyer code.  He’s encouraged me to go out on a limb and code features I probably otherwise wouldn’t have, making the code what it is today.  Oscar says that he will be creating a webpage detailing his work, probably around Christmastime.

I haven’t been on the air much recently, but I did build and start testing a beta release of the OpenQRP OQtransceiver1 rig.

The rig and the OpenQRP project is the brainchild of Steve, K1EL, the creator of the venerable Winkey.  The OQtransceiver1 is a monoband CW 40m unit, featuring NE602s in a superhet design with a narrow CW crystal filter in the receive chain.  The radio control is Arduino / ATMega328 based and the firmware is open source.  The OQ1 features a CW keyer, frequency counter, RIT, memory keying, two line backlit LCD display, and a CW decoder. Output power is slightly more than 5 watts.  The PC board and case is very professional looking and well designed.  I’m hoping to contribute to the OpenQRP project with firmware code updates and new features in the coming months.  I think the OpenQRP project is a nice concept that will likely produce some neat and innovative gear in the coming years, and provide another outlet for learning in this great hobby of ours.

The FCC has released a second Report and Order, affirming its rules for Broadband Over Powerline (BPL).  The document is available here.  It’s quite a lengthy mind-numbing read, but skimming through it, it appears the FCC has rejected changes to its previous findings over the past several years.  Undoubtedly ARRL will have much reporting and analysis over the next few days.  

After eight years of trying to take hold, Internet access BPL has for all intents and purposes become a dead technology, not even being mentioned in recent FCC broadband reports.  The BPL industry has been attempting to make inroads into so-called Smart Grid technology which will upgrade and automate electrical distribution networks.  I haven’t been following this industry closely, but last I had looked they didn’t appear to be having much success.  However the love affair with BPL at the FCC, and the OET in particular, lives on.

The Arduino project announced some news at MakerFaire 2011.  Here’s a video of a talk from Massimo Banzi:

In a nutshell, they are working on a new release of Arduino called “1.0″ or the “1.0 Core” which is going to break some things, but also set the stage for a more consistent and stable platform going forward.  There are new hardware revisions for the Uno and Mega boards.  The most notable change with these boards is the addition of several pins to support a two wire interface (I2C) bus which will enable much easier and standardized interfacing to shields.  There is also a new Arduino that has an Ethernet interface built in, rather than having to use a separate Ethernet shield.  (Shields are optional boards you can stack on Arduinos for additional capabilities.)  I’m very interested in this board as it also has an SD slot for memory storage.  I’ve been toying with the idea of writing a logger module for the keyer project.  Why?  Because I can and it’s never been done :-)

The project is also releasing a WiFi shield which opens up a lot of possibilities.  Another dream geek project I’ve had has been to place Arduinos in various places throughout the house and the yard for doing various things like reporting the temperature or sensing intruders.  The Arduinos could network via WiFi and report to each other or back to the mothership.

All and all it’s an exciting time in Arduino land.  If you haven’t tried using one of these little boards, you’re missing out on some fun.  The applications in amateur radio are endless and with the power and functionality steadily increasing, I expect in a few years we’ll be doing things like DSP or perhaps have a rig-on-a-shield.

Last month, Ernest, AA1IK, wrote about a frustration that we’ve all experienced, an operator on the other end who needlessly sends unnecessary information.  In the particular QSO Ernest described, the other op totally botched a QSO in bad QSB (fading) conditions by repeating his callsign numerous times but sending their call only once or twice.  The barely-uttered callsign was consumed by QSB on each return, propagation closed, game over.

Most radio amateurs understand the value of getting the most signal out and being able to pick signals out of the mud on receive, going to great lengths to improve antenna systems and buying great rigs with good receivers and linear amplifiers to get more signal.  However, it seems many don’t understand basic information transmission and the value of time, or perhaps better stated, the value of airtime.

I see this quite a bit during Field Day.  Operators in search-and-pounce mode will say or send the callsign of the station they’re calling, despite there being only one station on frequency calling CQ.  Stations calling CQ when getting a weak caller will spend forty seconds telling the station they didn’t get their full callsign and list the several possibilities they thought it was.

The practice is even more annoying in emcomm.  Ever hear a station take 120 seconds to tell a SkyWarn net control that it’s raining at their house but otherwise there’s nothing reportable happening?

The amount of information that can be conveyed is a function of the rate of communication (baud rate/wpm), the noise on the channel (signal-to-noise ratio), and the time available to communicate.  Talk faster or send CW at a faster rate and you can send more information in a given amount of time.  If the signal to noise ratio is low, you may need to send or talk slower (perhaps using more phonetics) and you’ll need more time to communicate the same amount of information.  Sending redundant information not needed for “error correction” or information already known by the receiver is a waste of communication channel time.  Those familiar with digital communications will recognize the parallels between digital protocols and algorithms and what I’m describing above.

Phone operators and really any radio amateurs who want to understand efficient radio communication should listen to their local 911 dispatch frequencies.  Airtime is very valuable, and wasting it can result in lost property and lives.  You’ll hear exchanges like this after a page goes out and a unit is responding:

Fire company unit: “County 901.”

County Control: “County.”

Fire company unit: “901 responding.”

County Control: “901 responding, 123 Main Street, dwelling fire.”

Fire company unit: “In route”

County Control: “Nineteen twenty-three”

In this exchange the unit informed county they were responding, they got the information on the call, and county confirmed the whole exchange with the time at the end.  Granted, public safety communications are usually on clear channels with little noise, but can you imagine some of the exchanges we hear on amateur radio in a public safety environment?

CW operators tend to be more efficient by default as the CW mode naturally encourages a level of terseness that’s not intuitive in phone operation.  But some CW operators in weak signal and contest situations have room for improvement, needing to avoid needless callsign repeating, “URs” and “QSLs”.

This lack of understanding by many in amateur radio of the value of airtime and how to use it efficiently is one of my ongoing pet peeves.  To some extent I can understand in this day and age why a radio amateur may not be well versed in complex electronic theory, but communicating efficiently is basic and it doesn’t take much to learn how to do it, people just need to apply some logic, listen, and learn.

This week amateur radio came through again, responding to the tsunami disaster at Wasabi Island.  Wasibi Island is a little-known island in the south Pacific inhabited by about 300 people which suffered a devastating category nine tsunami two weeks ago.  Wasabi Island is also a rare DXCC entity, having been in the top 15 most wanted DXCC entities list for nearly two decades.

The Pileup DX Society reacted quickly to the disaster.  Bob Peters, president of the esteemed society, assembled a crew within days of the disaster.  ”After hearing about the disaster we called up our top donors and within hours we had a team assembled.”  The Wasabi team was luckily able to quickly book commercial flights into Chile and charter a cargo ship in Santiago.  They landed on the beach on Wasabi Island three days later.  Within hours they were on the air with many amateurs in North America and Europe working the phone and CW stations on 20 meters, bagging the rare DX country.

“The island is devastated” informed team leader Tom Biznosky over a satellite phone call.  ”There’s no power on the island and no clean drinking water.  Luckily we brought generators, and plenty of fuel and water, so we can easily operate the stations for the next two weeks.  Sleeping conditions on the island have been awful, so we’ve been shuttling operators to the ship where they can get showers and sleep in air conditioning.”

The disaster conditions have made things difficult for the team.  ”The island has been flattened, so it has been very difficult to find any trees to string up dipoles on the lower bands.  On top of that, one of our 12 linear amplifiers which were donated stopped working.  The 10 meter phone station has been running barefoot.” said Biznosky.  ”But despite the setbacks, out team remains in good spirits.”

Amateurs are asked to stay clear of the Wasabi island frequencies as all stations are operating split.  Amateurs should go between 5 and 50 kilohertz above the Wasabi Island transmit frequencies when making their calls.  Look for Wasabi on all bands, on CW, phone, PSK and RTTY.  QSL direct to the QSL manager shown on the Pileup DX Society website (click on Wasabi Island disaster).  Donations to support the operation may also be made on the website.