Ten Tec is an American manufacturer of all sorts of radio equipment based in Tennessee. They make a neat little black box which attaches to any PC via a serial port. The box, called the RX-320D, is a shortwave (general coverage) receiver that works very well indeed with performance rivaling more expensive desktop receivers. If you read Ten Tec’s advertising you’d think you need Windows based software to use this radio. Think again.
Hector Peraza has written Linux software which offers the same functionality as the Windows software provided by Ten Tec when you buy an RX-320D. The current version of his rx320 software is version 0.6.2, with source code available on his Sourceforge web page. I’ve used my RX-320D with Mr. Peraza’s code for quite a while now and I’ve been extremely satisfied. I also maintain the rx320 package in the Vector Linux Extra repository. I’ve also built Ubuntu packages which work well under Edgy Eft and should work under Feisty Fawn as well. For some reason my serial port stopped working under Feisty and I need to take the time to do some troubleshooting to find out why.
OK, I can imagine some of you wondering why anyone would bother with shortwave in this age of the Internet and satellite TV. The fact is that there is still very interesting news, information, and cultural programming that I seem to find only on shortwave radio. Even if some of what I listen to (i.e.: Kol Israel Radio news) is readily available online sometimes it’s just plain easier to listen off the air while multitasking: doing something else with my computer online. The rx320 software uses very few resources much unlike listening to real time streaming audio. I still think radio has its place.
Why a PC radio? First, I can maintain a nice database with the rx320 software that lets me go directly to a large variety of broadcasts with frequencies and times, all recorded based on my experience of what I can receive clearly at my location. I just right click on the virtual radio on my screen, click frequency database in the menu, choose my station listing, and pick what I want. There’s no meaningful limit on the number of stations I can record information about. Much like a spreadsheet I can sort my stations anyway that’s convenient at the moment with a click or two on a column header.
The second reason is Digital Radio Mondiale (DRM): digital shortwave broadcasting with audio quality equal to domestic FM broadcasts. (No, DRM thankfully doesn’t mean “digital rights management” in this case.) Receiving digital signals requires an additional audio cable running between the IF output of the radio and the input to your computer’s sound card. I’ll be posting an article about dream, the free Linux DRM decoding software, in the not too distant future. While all in one digital shortwave receivers exist they are still relatively few, relatively expensive for what they are, and generally don’t work as well as the RX-320D.
What’s available on shortwave radio nowadays? English language broadcasts come from such diverse sources as Voice of Turkey, Radio Tirana (Albania), Radio Taiwan International, RAI International (Italy), Voice of Vietnam, Radio Ukraine International, Radio Netherlands, and so on. The list is very long even with the simplest of antennas: a wire run out my window into the trees along the side and back of my home. If you speak languages other than English then your choices multiply exponentially. The perspectives you hear on international broadcasts are often nothing like you’ll get from domestic media, at least here in the U.S.
Digital (DRM) broadcasts for North America include Deutsche Welle (Germany), China Radio International, Radio Netherlands, BBC World Service, and Radio Canada International. Folks in Europe have a much wider selection. There are times you can receive and decode digital broadcasts intended for Europe in North America and vice versa.
Digital Radio Mondiale broadcasts are all or nothing: you either get a perfectly good signal or they don’t get decoded at all. The sound quality is good enough for music. (OK, some people do listen to music on old fashioned analog shortwave, which is kind of like listening to music on AM radio at best.) My hope is that more of the international broadcasters who do play some interesting music from their home countries begin to add digital broadcasting to their schedules. I also hope American broadcasters (other than the Christian religious broadcasters who currently dominate U.S. shortwave signals) decide to get on the air. The FCC allowed for U.S. DRM licenses last year.
For those familiar with some of the more sophisticated commercial Windows software for the RX-320D (i.e.: Scope Station), alas there is no Linux equivalent. For the moment we are limited to basic RX-320D software until some clever Open Source developer decides to write something better. Still, I don’t feel like I’m missing anything using Linux software with my RX-320D.