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Shortwave Radio and The PC
An anonymous reader writes "Ars Technica has an indepth guide on the Ten Tec RX-320, a shortwave radio receiver that connects to the PC and is controlled by software (both Linux and Windows). The article goes into depth on different high frequency modes, broadcast shortwave, and even a bit on ham radio and new digital modes."
The Javaradio (http://www.javaradio.com) setup is based around the Icom PCR-100 or PCR-1000. If I recall correctly, Yaesu do one too.
Whether the PC causes RF problems with reception depends on the PC. I was using a Mac alongside a ICOM receiver between 1989 and 2001 with no problem whatsoever -- from the Mac. The neighbor's microwave oven was another matter entirely. I always knew when they were defrosting stuff. I don't know about other PC's -- maybe someone else can comment on that?
Internet radio taking over shortwave, maybe, in some ways. They really are two different media, though, with different strengths. And there are still places in the world where not that many people have access to a computer or an ISP, but they still may have an old SW set to listen to the BBC.
(And for the romanticist, there's nothing like listening to a cricket match between Fiji and the Solomon Islands teams over Solomon Islands radio, commented in Pidgin English, by the glow of shimmering tubes!)
OK, now what?
To all those who thought that SW went out with Churchill and Franklin D.: SW is not dead.
In some countries like Africa, SW radio is the only medium that a population that might not be able to read can rely on for information/education. See hoe the success of the Clockwork radios depended on Charitable organisations using them in continents where electricity supplies were rare.
SW radio is still the only way you can listen to radio in some places, simply because of the durability of the signal over long distances, and the relatively low cost of equipment.
Hang on, then why the hell would I want to attach one to a PC? Surely even the pleasure of DXing doesn't get augmented with use of the PC.
Now where's my morse-button...?
Smokey, this is not 'Nam, this is bowling. There are rules.
Hams have been doing packet radio for decades.
Amateur radio support (aka AX.25) is already present in the Linux kernel and has been for some time.
My journal has hot
A new digital standard for SW/LW/MW will officially launch this time next week, DRM is based upon COFDM (as per DTV in Europe, 802.11a/g etc) and uses the AAC codec at around 30kbps, it doesn't sound much but it's an amazing improvement upon analogue shortwave and will really bring it back to life again, instead of being the preserve of nutters living in huts in Montana.
Anyway, checkout the samples, not bad for a signal that has travelled to and from the extreme of Europe.
That's been done, it's called Packet Radio.
IIRC, there is support for it in the more recent Linux Kernels (as a module).
I've seen some small Packet Radio setups but it doesn't seem to be as popular as it could be (for reasons a packet radio nut should probably explain)
WorldStation is Java-program and it's listed as Mac OS X-software, so I think there's only problem that those RX-320 boxes have serial ports. There are some USB-to-Serial-converters for Macs, so it's not big deal either.
Remember that Macs can run Linux as well. And another solution is to run VirtualPC-emulation for Windows.
And if those system ever hit mainstream, there will be native Mac solutions as well, but that's not likely.
See this Linux Journal article ca. 1995:
http://linuxjournal.com/article.php?sid=1071
Ask me about my vow of silence!
Pointless? Internet radio is gonna take over shortwave? I don't think so. Not for a long time. Thought about using some mod points to mod this parent as a troll. But then figured i could simply point out that, as soon as you can get computers to the entire third world, then you can start talking about the death of shortwave as a source of news and programming.
.04
No doubt other technologies are developing rapidly. Actually, internet radio is just one. But shortwave is still the only way for people to have ready access to information in the third world (which is a *large* part of the world).
The amount of good shortwave programming is less than it once was (BBC no longer directs a sw broadcast to the states, DW is stopping its broadcast to the US sometime soon), but it still is quite strong.
Head over to usenet and check out the sw groups. Considerable numbers of posts everyday from new users wanting to know what radio to take when they head somewhere out of their country of origin. My sister lives in Berlin. I got her a cheap sw radio so she can readily listen to BBC, VOA, and AFR. Gives her more option of english language programming besides CNN that she might not otherwise get. Pick up a copy of "Passport to Worldband Radio" and you'll see all the programming that is out there, not accessible via internet radio.
Anyway, I could go on and on and on. The point is that the medium is hardly dead. Not what it once was to be sure, but a very viable (and vibrant) broadcast community still exists, and will exist for some time to come. Its a good way to get a variety of opinions, from a variety of broadcast outlets, not to mention the *high* geek factor that is involved in the hobby.
my
jeff
A world wide wireless internet cannot be censor.
Yes it can, just create a lot of interference.
Its not even that hard to do (when you consider that its governments that might want to do so).
You might also like to do a bit of research into what sunspot activity does to short wave radio transmission.
TenTec's RX-320 is a solid rig, but a bit dated. Newer receivers, such as the Icom PCR1000, outperform the RX-320 in every way (VFO speed, frequency coverage, receive modes, sensitivity, filters, notch, etc). Of course it costs more than twice as much, but you get more than 1 Ghz additional receive coverage (100 kHz - 1.3 GHz), which allows it to be used as a scanner, and not just a SWR.
Dan East
Better known as 318230.
Anyone who says that shortwave is dead and pointless have obviously not listened to SW broadcasts coming out from the Democratic People's Republic of Korea. And I challenge you to find it streamed live on the Net. Nothing beats hearing first hand (or first ear?) to propanganda. In the future, where every country and every civilization on the planet has access to the Internet, then yes, SW will be dead. But until then, SW remains the best form of receiving information (or propanganda) about places with no Internet connectivity.
Thanks to Hemos for the TenTec info. Check out the following sites for info on PC controlled receivers that do not suffer from internally generated noise. These guys have done a great job. http://www.linradio.com/ and http://www.winradio.com/ The g303i is the receiver to go for if you just want HF reception. Other units go to 4GHz! Some receivers are external and some internal ie they mount in your PC! http://www.winradio.com/home/g303i.htm You may recognise some of their kit from the Paris Safe House in The Bourne Identity. Note the open software development unlike better known oriental brands.
My hyperlinks aren't worth the paper they're printed on.
TCP/IP can be routed over packet.
Of course, the issue is "Would you want to" on HF. (aka shortwave)
The answer is No, unless you're on some remote island in the South Pacific where there are no phone lines and satellite connections are multiple $$$ per minute, in which case a 1200 (or slower) bps connection is a godsend.
The legal limit on channel bandwidth in most HF bands is on the order of 3-6 kHz (Enough for SSB voice). Since there's lots of noise on HF, advanced modulation schemes that allow you to stick more than 1 bps per Hertz usually don't work. Most HF data connections are 2400 bps or less. (300 bps is quite common, and currently the most popular digital mode is PSK31 at 31 bps, due to its bandwidth being narrower than Morse and having superior noise immunity to any faster data mode.)
retrorocket.o not found, launch anyway?
Why settle for an HF radio that's merely computer-controlled when you can make the computer the radio. Gerald Youngblood's SDR-1000 is a full-blown Software Defined Radio (SDR) that blows away most ham rigs. The demo Gerald did at Dayton was very impressive. The best part is that if you want your radio to have a new feature, all you have to do is write the code to do it...
--zawada
In Soviet Russia, the Beowulf cluster imagines you!
I had the same problems with packet that you mentioned. I was doing 1200 bps on the 2m band. It was pretty much useless for anything beyond quickie text messages. I heard about people doing 110 bps on shortwave. The ability of shortwave signals to bounce off the ionosphere was much more useful before we had all these communications satellites and global fiber optic networks.
I don't think we will ever see the stability or bandwidth to make shortwave support anything that geeks would consider useful. Ham satellites are a little more promising. If we had a Wifi via Ham satellite, now THAT would be fun.
There's absolutely no comparison (yet, in widespread useage) when it comes to scaling and cost. I can purchase commercial shortwave air time for as little as 25$ an hour side band upto around 100$ or more for full duplex from huge whopper powerful transmitters, the data can be received by millions of people. And if it's non commercial from my own rig, it's upfront hardware cost, then just some electricity cost,that's it. Now,to contrast that, go to any net broadcaster you can find,either MP3 or Real or quciktime, etc, pick any of those,now see what a million streams at even very, very low bit rates (say 16kbps-vocal, talk radio) cost. Go ahead, check it out. Now try it at 128kbps(somewhat decent music quality).
Granted, shortwave hardly ever has that sort of high fidelity quality associated with it, but, it works for inside the parameters for what it's designed for, no way does the ole intarweb come close yet. It has potential, but it ain't there yet. Technically it's possible, cost wise it's just way out of sight. I know there are peer to peer streaming technologies, I have played around with one of them (streamer), but it's very far from even say the level of acceptance of OGG as a generic format standard, ie, "real darn low". I would like there to be more interest and development in that sort of project, but most people only want a clear channel experience, or to download mp3 files..
Shortwave is still most useful, as well as radio in general. The main reason is-it works, doesn't require anything in the way of outside infrastructre to work and reach theoretical millions. Ain't no wirez in the middle anyplace absolutely positively needed, and receivers are as cheap as under 50 dollars new.
I grew up on shortwave radio from the 60's, 70's as a kid. I remember the first time I listened to one, got hooked on it, studied and passed my amateur test and got licensed. No, the PC won't cause interference, unless you have it sitting on top of your computer, the receiver is an external box. I've been hearing the death of sw/ham radio for years. Everyone has been saying ham radio is dying.....well, they said the same thing about CW (morse code), but it's still around. Plus, you think the manufacturers of amateur radio gear are in a money loosing business? Doubt it.....every few months I get a catalog with all the new gear....they build it, people are buying it.
However, if you use the UHF, VHF, and microwave bands. (WiFi btw is basicly just what we're already talking about on the microwave bands) then a lot more spectrum opens up. The problem with these bands is they do not skip the way the SW bands do so cannot cross long distances. Your maximum range is about 10% beyond the horizon. However, if you stratigicly placed routers/repeaters over a country, you might be able to give that entire country a wireless computer network, just don't do peer-to-peer filesharing or other high bandwidth tasks on it please. Interfearence could be partial overcome by using many, many different bands so that traffic could be spread out over 20-50 different frequencies or so.
73
KG4WWN
Little Brother, watching the watchers
Compared to what we can do in this Google Age, it is harder to find good stuff on SW. But that doesn't mean it's not there.
One of the best ways to get started is the book "Passport To World Band Radio" with this book you can tune in to right frequency at the right time which is important. I could never get a station until I got this book. Highly recommended. [http://www.passband.com]
The BBC World Service has some great programs and other stations for English programming include Deutsche Welle, Radio Netherlands, Radio Austria International, Voice of Russia, Radio Canada International, and the Voice of America.
Yep, and since we were doing it over radio we had wireless networks long before the rest of the computer world caught up. Packet radio was good for email and jumping digipeaters but not very good for file transfers. TCP/IP networks were available in many areas that went a little farther than the standard ax25 networks that most hams used. Also there is a lot more than just music and news broadcasts on shortwave. Spy stations and digital diplomatic traffic are there as well as a host of other things to listen to. The digitally controlled receivers make listening to and decoding these signals much easier. As far as noise goes it depends on how well built the PC you are using is....as stated before Macs seem much better for this purpose....less RF interference. Even if the programs are for windows, Virtual PC will run them just fine.
Two things that are certainly NOT dead: Shortwave and BSD. Visit the page at: DSP radio for LINUX on Intel platforms
It's a beautifully documented, state of the art, software-defined, digital signal processor. It's downloadable and it's free! (Yeah, I know that Linux is not BSD, and vice versa. But this radio runs under both. Okay?)
My favorite is the Ten-Tec Pegasus. Why? Because you can receive AND TRANSMIT (with appropropriate Ham license) on all the frequencies using your computer and the interface box. Heck, they even include source code! The product name is "Pegasus". Check it out: http://www.tentec.com/TT550.htm