Category Archives: Articles

AirChat: Long-distance digital communications via radio

AirChatLogo-001Last month, I was interviewed by NK News regarding the possibility of using inexpensive SDR dongles as a means for citizen journalists to receive and potentially send information across the North Korean border. Of course this is possible: digital communications over radio is becoming easier and more accessible all of the time.

While not yet as portable as an SDR dongle, Anonymous is developing a tool called AirChat which will allow long-distance communications via radio. AirChat borrows from Fldigi: a free application that decodes a variety of digital modes and has been used by amateur radio operators for years. Indeed, Fldigi is the same software you’ve used to decode broadcasts from VOA Radiogram and the new STF Radio.

Many thanks to the excellent  Southgate ARC news site for this article about AirChat:

(Source: Southgate ARC)

The International Business Times reports that the online hacktivist collective Anonymous has announced that it is working on a new tool called Airchat which could allow people to communicate without the need for a phone or an internet connection – it uses radio waves instead 

Initially the data mode software AirChat used code from ‘minimodem’ and then from ‘soundmodem’ sources but they say after suggestions from radio amateurs involved in the Amateur Radio Emergency Service (ARES), they decided to make it modular to use the Fldigi software, a broadly deployed solution for use with ham radios.

They say “So far we have played interactive chess games with people at 180 miles away. we have shared pictures and established encrypted low bandwidth digital voice chats. We have 3D printed over distances of 80 miles and transmitted medical orders at distances of over 100 miles.”

So far Yaesu FT-897D’s amateur transceivers have been used and the developers are also looking at using low-cost ($40) VHF/UHF handheld transceivers.

Read the International Business Times story 
http://www.ibtimes.co.uk/anonymous-airchat-aims-allow-
communication-without-needing-phone-internet-access-1445888


LulzLabs AirChat
https://github.com/lulzlabs/AirChat/

You can read about the goals of AirChat on their Github site and follow AirChat on Twitter with the hash tags #lulzlabs and #AirChat.

Anonymous has also posted the following video–a demo of AirChat:

Airchat from #lulzlabs on Vimeo.

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Shortwave.am: a new online frequency guide

ShortwaveAMA few SWLing Post readers have recently recommended that I check out a new shortwave radio schedule site: shortwave.am.

Shortwave.am has a unique layout that lists broadcast schedules along with a map that displays broadcast footprints (both short and long path).

Fortunately, I was able to get in touch with the site developer, Stephen Cooper, who frequently comments on the SWLing Post.

Stephen kindly answered a couple of questions I posed.

My first question was why, with the number of shortwave schedule sites on the Internet, he felt motivated to create a new site.  Evidently, inspiration came from Stephen’s Android app, Shortwave Radio Schedules. He responds:

I first created the [Shortwave Radio Schedules] app to give me searchable listings on my phone which I found interfered much less with my radio than on my PC so I could turn my PC off and look at frequencies and schedules on a phone/tablet.

Since then I have just added extra features that I find useful, such as the ability to save logs including the station name, time, SINPO, a comment and a recording of the audio. I’ve used the app to then share my logs to Facebook groups, DXLD Yahoo Group etc. including the audio recordings made on the app.

The maps option I added because I had been using AOKI listings with the beam direction to try and work out favourable beam directions of broadcasts for me in the UK even if they were not targeted to Europe. I realised that it would be much easier to visualise this on a map and started looking at the Google Maps API to work out this would be possible on the app.

Once I added to the app I had noticed screenshots of the maps being posted on groups such as the Rally DX 2012 Facebook group’s and a few people who didn’t have Android asking if there was a web version. I looked into it and it wasn’t too hard to create shortwave.am after converting the Java code to PHP:and Javascript then the site was complete.”

When I asked Stephen what made his site differ from others, he responded:

“[I]t uses data from a combination of Eibi and AOKI to display the listings with maps showing the beam direction. It can also show estimate long paths of each broadcast and uses AJAX web technologies to show search results and maps without having to reload the page for each search or change of parameters.

[…]If you choose a station or language or both and click “Save” (next to the “Set Defaults” part of the site) it will set these as the default that will open each time you go to the site.

Also if you click on a transmitter it now shows all broadcasts coming from that transmitter.

[…]I am going to add some more of the features from the [Shortwave Radio Schedules] app such as the ability to add logging reports, view others reception reports from each station and the options to add recordings of a station and listen to others recordings.”

I think shortwave.am is fantastic, and I’m glad Stephen has put the time behind developing it in his spare time.

Stephen is eager to hear your comments, as he wishes to further develop the shortwave.am. Either post them here, or email Stephen directly.

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The Radio New Zealand coastal forecast

(Source: stuff.co.nz)

In response to my post on the BBC Shipping Forecast, SWLing Post reader Mark writes:

I just read your latest blog about the BBC marine forecast. It sounds very similar to the RNZ coastal forecast…..but they also have a mountain forecast!

http://www.radionz.co.nz/news/weather/coastal

Broadcast times

  • Short: with hourly news bulletins
  • Regional: 5:30, 6:32am on weekdays, and 5:30am and 7:05am on weekends
  • Main centre: 5:05, 5:35, 6:08, 7:08, 8:08am on weekdays and 5:05, 5:35, 6:05, 7:05 and 8:08am on weekends
  • Urban: 7:32, 8:32am
  • Long-range: 12:32pm on weekdays and 1:04pm on weekends
  • Coastal: 4:05am
  • Mountain: 4:05pm

Many thanks, Mike! I had no idea New Zealand had a coastal forecast similar to that of the UK. I shouldn’t be surprised, though, as New Zealand is very much a maritime country and indeed, Aukland, NZ has the highest boat ownership of any city in the world.

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And now, the Shipping Forecast…

shipping-forecast-locations

When I lived in the UK, I would often fall asleep and/or wake up to the Shipping Forecast: a BBC Radio broadcast of weather reports and forecasts for the seas around the coasts of the British Isles.

Though I had, of course, no real need of the Forecast, on many occasions it lured me like the voice of a hypnotic siren (especially, I must admit, when read by a woman). When I moved back to the US in 2003, I missed hearing the Forecast on the radio, but thankfully one can listen to it at Radio 4 online. Although the online stream lacks the delectable sonic texture of long wave radio, the Forecast still has the power can still reel in its listeners.

Last December, I followed a brilliant series on NPR which highlighted the BBC Shipping Forecast.  I intended to publish it here on the SWLing Post at the time, but somehow lost it in the shuffle of a busy travel season. Fortunately, NPR has archived audio from the series online. I love their introduction:

“It is a bizarre nightly ritual that is deeply embedded in the British way of life.

You switch off the TV, lock up the house, slip into bed, turn on your radio, and begin to listen to a mantra, delivered by a soothing, soporific voice.

“Viking, North Utsire, South Utsire, Forties, Cromarty, Forth, Tyne, Dogger ….” says the voice.

You are aware — vaguely — that these delicious words are names, and that those names refer to big blocks of sea around your island nation, stretching all the way up to Iceland and down to North Africa.

The BBC’s beloved Shipping Forecast bulletin covers 31 sea areas, the names of which have inspired poets, artists and singers and become embedded into the national psyche.

Your mind begins to swoop across the landscape, sleepily checking the shorelines, from the gray waters of the English Channel to the steely turbulence of the Atlantic.

Somewhere, deep in your memory, stir echoes of British history — of invasions from across the sea by Vikings, Romans and Normans; of battles with Napoleon’s galleons and Hitler’s U-boats.

Finally, as the BBC’s Shipping Forecast bulletin draws to a close, you nod off, complacent in the knowledge that whatever storms are blasting away on the oceans out there, you’re in your pajamas, sensibly tucked up at home”

You can listen to the series on NPR, or via the embedded player below:

Click here to listen to the Shipping Forecast on the BBC Radio 4 website. Also, check out the history of the Shipping Forecast on Wikipedia and from this excellent article by Peter Jefferson in Prospero (PDF, page 10).

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International SW Disaster Test: June 4-5, 2014

300px-Hurricane_Isabel_from_ISSSWLing Post reader, Mehmet Burk, has just published information about the upcoming international disaster test on shortwave radio, coordinated by the High Frequency Coordination Commission (HFCC) for the International Radio for Disaster Relief project.

Mehmet has details of this June 4 – 5 international radio event on his website: Relief Analysis Radio.

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Traveling light, SWLing right: the best shortwave radios for travel

This article originally appeared in the March 2014 issue of The Spectrum Monitor Magazine.


SWL Travel Gear - Grundig G6

With spring around the corner, my thoughts drift toward the outdoors…and especially, toward travel. Those who know me know that I love travelling, anywhere and everywhere–and that I prefer to travel light, with only one bag. In fact, I can easily live for two weeks out of a convertible shoulderbag/backpack (the Timbuk2 Wingman) that’s so compact, I can fit it under the the seat of even the smallest, most restrictive aircraft. I never have to check luggage unless the nature of my travel requires extra supplies (I run Ears To Our World, a non-profit that donates radios and other technologies to powerless regions in the developing world).

My Timbuk2 Small Wingman is very compact, yet holds everything I need--including radio gear--for two weeks (or more!) of travel.

My Timbuk2 Small Wingman is very compact, yet holds everything I need for two weeks (or more!) of travel.

So, why not pack everything you could possibly ever want on a journey?  While this remains an option, travelling light has many advantages over the take-it-all traveler’s method. First, it gives one incredible freedom, especially when travelling by air or train.  I never have to worry about being among the first to be seated in an aircraft, nor do I worry about my luggage not making a connection when I do.  Second, it’s kinder on the back and shoulders, and easier to maneuver wherever I go–no wheels required–whether in a busy first-world airport or bustling third-world street market.  Third, I always have my most important gear right there with me.  And finally (I must admit) I find light travel to be fun, an entertaining challenge; the looks on friends’ faces when they meet me at the airport to “help” with my luggage is, frankly, priceless.  Seeing me hop off a flight with my small shoulder bag, friends ask in bewilderment, “Where’s your stuff?” It’s music to my ears.

You would think that having such self-imposed restrictions on travel–carrying a small, light bag–would make it nearly impossible to travel with radio. On the contrary!  Radio is requisite, in my book–er, bag.  I carry a surprising amount of gear in my small bag:  once at an airport security checkpoint, an inspector commented, “It’s like you have the contents of a Radio Shack in here–!” But more significantly, each piece–and radio–is carefully selected to give me the best performance, durability, versatility, and reliability.

So what do I look for in a travel radio? Let’s take a closer look.

SWL Travel Gear - full selection

Travel Radio Features

While the CountyComm GP5DSP only has average performance for its price class, it has three different ways of auto tuning stations quickly, an alarm function and the display will even indicate the current temperature. Its unique vertical, thin body might be easier to pack at times, depending on your travel gear.

The CountyComm GP5DSP has three different ways of auto tuning stations quickly, an alarm function and the display will even indicate the current temperature. Its unique vertical, thin body might be easier to pack at times, depending on your travel gear.

In a travel shortwave radio, I search for features I wouldn’t necessarily pick for home use, where I’m mainly concerned with raw performance. I don’t want to carry an expensive receiver while traveling, either: $100.00 US is usually my maximum. This way, if I accidently break the radio (or my gear gets stolen), I won’t feel like I’m out very much money.  I also prioritize features that benefit a traveler, of course; here are some that I look for:

  • Small size: Naturally, it’s sensible to look for a travel radio that’s small for its receiver class for ease in packing.
  • Overall sturdy chassis: Any travel radio should have a sturdy body case that can withstand the rigors of travel.
  • Built-in Alarm/Sleep Timer functions: While my iPhone works as an alarm, I hate to miss an early flight or connection, so it’s extra security when I can set a back-up alarm.
  • Powered by AA batteries: While the newer lithium ion battery packs are fairly efficient, I still prefer the AA battery standard, which allows me to obtain batteries as needed in most settings; a fresh set of alkaline (or freshly-charged) batteries will power most portables for hours on end.
  • Standard USB charging cable: If I can charge batteries internally, a USB charging cable can simply plug into my smart phone’s USB power adapter or the USB port on my laptop; no extra “wall wart” equals less weight and less annoyance.
  • ETM: Many new digital portables have an ETM function which allow auto-scanning of a radio band (AM/FM/SW), saving what it finds in temporary memory locations–a great way to get a quick overview of stations.  (As this function typically takes several minutes to complete on shortwave, I usually set it before unpacking or taking a shower. When I return to my radio, it’s ready to browse.)
  • Single-Side Band: While I rarely listen to SSB broadcasts when traveling, I still like to pack an SSB-capable receiver when travelling for an extended time.
  • RDS: Though an RDS (Radio Data System) is FM-only, it’s a great feature for identifying station call signs and genre (i.e., public radio, rock, pop, country, jazz, classical, etc.)
  • External antenna jack: I like to carry a reel-type or clip-on wire external antenna if I plan to spend serious time SWLing. Having a built-in external jack means that the connection is easy, no need to bother with wire and an alligator clip to the telescoping whip.
  • Tuning wheel/knob: Since I spend a lot of time band-scanning while travelling, I prefer a tactile wheel or knob for tuning my travel radio.
  • Key lock: Most radios have a key lock to prevent accidentally turning a radio on in transit–but with a travel radio, it’s especially important to have a key lock that can’t be accidentally disengaged.
  • LED flashlight: Few radios have this, but it’s handy to have when travelling.
  • Temperature display: Many DSP-based radios have a built-in thermometer and temperature display; I like this when I travel anytime, but especially when I’m camping.

While I don’t have a portable that meets 100% of the above travel radio wish-list, I do have several that score very highly.  I also rank my travel radios by size, as sometimes limited space will force me to select a smaller radio.

Here are a few of the radios I’ve used and/or evaluated for travel–I’ll break them down by size. Note that all portable radios have alarm/timer functions, unless noted otherwise.

My Tecsun PL-380 and the small Eagle Creek pack that also holds my Zoom H1 recorder, earphones, audio cables, external antenna, spare batteries and Kindle.

I often grab the Tecsun PL-380 for travel. It’s an ultra-portable that truly performs and even has a selection of six AM bandwidths.

Ultra-portable:

Tecsun-PL880-SWLing-Post-0528

Full-Featured Portable:

I have also been known to travel with an SDR (software defined radio), especially if travelling to an RF-quiet location where I could make spectrum recordings. While SDRs all require a computer (laptop) to operate, those best suited for travel derive their power from the same USB cable plugged into the PC. Neither of the SDR models below require a power source other than what’s provided by their USB cable.

A screen capture from my Toshiba Satellite Windows 7 laptop (click on image to enlarge)

The RadioJet is an excellent travel radio: it’s an excellent performer, über-rugged and is powered by one USB cable.

“Black box” radios (SDRs & PC-controlled radios):

  • RFSpace SDR-IQ • Pros: Small size, works on multiple operating systems (Windows, Mac, Linux) • Cons: front end can overload if close to strong signals
  • Bonito RadioJet • Pros: Great performance, low noise floor, good audio, flexible graphic interface; • Cons: Windows only, limited bandwidth on IF recordings, no third-party applications (note that the RadioJet is technically an IF receiver). Check out our full review.
The CommRadio CR-1

The CommRadio CR-1

Tabletop:

Seriously? A travel-ready, full-featured tabletop–? Until last year, I would have argued that it was impossible to travel lightly with a full-featured desktop radio in tow.

My view changed when I got my hands on the CommRadio CR-1 tabletop SDR. Indeed, other than it being pricey ($600, as compared with $100 portables) this rig is ideally suited to travel!

The CR-1 has an array of features–most everything you’d expect from a tabletop radio–and even covers some VHF/UHF frequencies. Its built-in rechargeable battery not only powers it for hours at a time, but meets the strict airline standards for battery safety. The CR-1 can also be powered and charged via a common USB cable. It’s also engineered to be tough and is almost identical in size to the Tecsun PL-880.

CommRadioCR-1PowerKnobThough I’ve never needed to do so, you can even remove its resin feet to save still more space. Its only less than travel-friendly feature is the fact that it’s quite possible to accidently power up the CR-1 by bumping the volume button during travel–a problem easily remedied, however, by simply twisting an insulated wire around the stem of the volume knob (see photo).

The importance of a Go-Bag

The SpecOps PackRat

The Spec-Ops Pack-Rat

I keep a dedicated “go-bag” with radio and supplies–specifically, the Spec-Ops Brand Pack-Rat–packed and ready to travel, at the drop of a hat. Why? First of all, I know exactly what I’ll be taking, no need to ponder if I have everything.

Inside the bag, everything has its place: my portable SW radio, my Android tablet, my D-Star Icon ID-51a HT, DVAP (DV Access Point Dongle), my Zoom H2n Handy Recorder, earphones, charging cables, batteries, small notebook, clip-on wire antenna, etc.

If something’s missing, there’s an obvious blank spot in my bag. I also know exactly where and how it fits into my carry-on bag, so if it’s missing, it’s conspicuously missing. Since I’ve been using this go-bag, I’ve never left anything from my pack behind. Incidentally, this is how I pack the rest of my bag, as well: everything has its place, and any gap will draw my attention to exactly what’s missing.

SWL Travel Gear - Spec-Ops Pack-Rat Open

There’s another benefit to having a dedicated go-bag: when flying, before I place my carry-on under the seat in front of me or in an overhead compartment, I can pull the go-bag out of my carry-on and have my Android tablet close at hand with other electronics.  As an added bonus, when going through airport security, all of my electronics can be easily removed from my flight bag by taking out just this kit.

 SWL Travel Gear - Spec-Ops Pack-Rat Contents

I’ve had many versions of the Go-Bag over the years, and they’ve all done a great job. What I love about the Spec-Ops Brand Pack-Rat, though, is the fact that it’s military grade–very durable–opens with all of the main storage pockets on the inside, has a bright yellow interior which makes it easy to see the contents (even in the dimness of a night flight), and it’s just the right size to hold my usual travel gear. The Spec-Ops Brand Pack-Rat also carries a lifetime, no-matter-what, guarantee.

There are thousands of similar packs on the market, and you may already have one, but you should look for something with multiple storage pockets. Small packs I’ve used in the past that only had one or two main compartments made it easy to leave something out when packing.

Radio travels

The travel radios I reach for most often. Top Row (L to R, Top to Bottom)  Tecsun PL-380, Sony 7600GR, CommRadio GP-5DSP, Grundig G6, Tecsun PL-660, and the CommRadio CR-1

The travel radios I reach for most often. Top Row (L to R, Top to Bottom) Tecsun PL-380, Sony 7600GR, CommRadio GP-5DSP, Grundig G6, Tecsun PL-660, and the CommRadio CR-1 (Click to enlarge)

When I spent a year in France during my undergraduate studies in the early 1990s, shortwave radio was my link with home. I would listen to the VOA–the only source of English I permitted myself to hear–like clockwork, each week. Today, although I travel with a smartphone which can tune in thousands of stations, I always choose to listen to radio. Besides, if the Internet goes down or if–heaven forbid!–your trip takes you into a natural disaster, it’s radio that you will turn to to stay safe and informed.

If you take anything away from this reading, I hope it’s that even when you’re presented with travel restrictions, you won’t hesitate to take your hobby, in the form of a portable radio and a few accessories along. It contributes measurably to the fun of travel, as I’ve discovered when I’m able to tune in local and international stations so different from those I hear at home.  Or sometimes, it’s just the opposite–it’s the chance to pick up a favorite broadcaster or program while you’re on the road.

After all, for me and other travelers like me, the world’s familiar voice is radio.

SWL Travel Gear - Full View

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Forbes: “How To Make Music (And Money) From Shortwave Radio”

RFNomadModularGridTwo weeks ago, we posted a video of Evaton Technologies RF Nomad: a modular synthesizer that employs shortwave radio to create unique sounds. As someone who has always been fascinating with music and the sonic texture of the shortwaves, of course I find this product fascinating.

Forbes magazine does too. This morning, @UlisK3LU shared an article in Forbes where Russell Hoffman, who runs Evaton Technologies, explains why he believes using shortwave radio in new RF Nomad will be a hit:

“What’s interesting about shortwave radio is that it isn’t necessarily musical by design, but there are interesting sounds to be found when the station tuning is less than perfect,” he said. “You can hear all sorts of sounds on shortwave, from voice, to music, to Morse Code or encoded digital transmissions. In addition to the sounds that are transmitted intentionally, there are sounds that are artifacts of the medium itself like heterodynes, pops, crackles, hiss, static crashes, fading and the like.”

But here’s my favorite bit:

“Shortwave radio has a long and storied history, full of intrigue, espionage, piracy, rebellion, propaganda, and subterfuge,” he added. “It propagates around the world and can be received on inexpensive equipment. It is universal, because it can be heard anywhere; and yet at the same time, in a world of internet, TV, and satellite radio, it is also the underground — a hidden world parallel to that of our daily experiences. It offers an additional perspective.”

I couldn’t have said it better myself. Thank you, Mr. Hoffman.

Click here to read “How To Make Music (And Money) From Shortwave Radio” in Forbes magazine.

Check out Evaton Technologies and RF Nomad announcements by clicking here.

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