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PCI Shortwave Receiver
payman writes "WiNRADiO Communications has just announced news of its forthcoming WR-G303i PCI based shortwave, digital radio, narrowband FM receiver. This is said to be "the world's first dedicated shortwave receiver on a PC card. It is also the first commercially available receiver where the entire final intermediate frequency stage and an all-mode demodulator are entirely executed in software, running on a personal computer." Winradio has in the past supported Linux for its products (see Linradio), and it most likely will continue to do so with the WR-G303i."
This looks pretty cool, and does 6Mhz AM, little known fact that you can listen to lightning storms on 6Mhz AM world wide. If forget the homepage of the group but there is a group using 6 Mhz AM and RDF equiptment to plot lightning strikes across the world. If anyone has a link to the group it would be much appreciated, can't even find it on google. --morph
If these guys have Linux support, then what is Eric Blossom doing with GNU Radio? And why have these two articles about SDR been posted today?
-russ
Don't piss off The Angry Economist
Since shortwave is more or less a party line with pure analog transmission,
There is plenty of digital traffic on HF.
what stops an unscrupulous person from spamming it and making it unusable to everyone else?
The ITU. Even though I do remeber Castro took 1510 WLAC here in Nashville, along with other stations on the East Coast, off the air around 1989 because of "TV Marti". (Sorry for no links. I'm lazy.)
--fatboy
An excerpt from NPR's Lost & Found Sound:
"Eventually, if listeners dig around [the shortwave spectrum] long enough, they'll tune across voices reciting endless strings of numbers. These broadcasts have been heard for at least 40 years. The signals are powerful, but they contain no information about location of the transmitter or the intended audience. Most listeners linger for a short time, then tune away, utterly baffled."
When I discovered these myself, I found them bizarre, chilling- and intriguing. In order to get some background, I ordered a 4-CD set from Irdial recordings in the UK called The Conet Project... highly reccomended.
What is perhaps the most surprising is that the number of numbers stations boradcasting on the shortwave band are only increasing- variously attributed to the increasing sophistication of organized crime, drug cartels, terrorist/separatist organizations and an increasingly fractious global intelligence community.
Do follow the links above if this intrigues you in the slightest- and just try going back to your insular world-view afterwards; "the enemy" is out there, and he's hiding right out in the open.
Snickersnee3: Build your own 3-watt Luxeon Star headlamp from scratch
Crack a "Numbers" Station ... until now!
The makers of "The Conet Project" (a four-CD set of numbers-station recordings) have thrown down the proverbial gauntlet and announced a
series of "cryptographic
challenges" -- the object of which is to crack an actual numbers station
broadcast. Dust off your Crypto caps, everyone -- I want to see a slashdotter win this one! "
Posted by Hemos on Sat 27 May 01:35PM
from the cool-insight dept.
boss soul writes: "On Friday, NPR did an excellent story on those infamous 'Numbers Stations' that broadcast on shortwave radio. Since the 1950s, these stations have been broadcasting nothing but an unidentified human voice reading a string of numbers. Though most people believe that these broadcasts are used by intelligence agencies to communicate with their agents abroad, there has never been any way to confirm this
Snickersnee3: Build your own 3-watt Luxeon Star headlamp from scratch
ham radio buffs are a thing of the past
i s. html
Ham radio hobbyists provide an important redundant channel that is extremely difficult to knock off the air. When the hurricanes and earthquakes are done, all a Ham needs is a car battery and a length of wire to make contacts all over the world. Here is an article on use of Ham radio during some problems on Mir:
http://www.hamradio-online.com/1997/jun/mircris
And here is one on activities associated with Isadore that are in progress as I type this:
http://www.arrl.org/
There are currently about 680,000 licensed ham operators in the US.
This a large number to relegate to the past..
I bet those same geeks were the first pepple on the internet and the early online services like compuserve in the late 80s)
Hams were much more likely to run their own BBS than hang out on a service like Compuserve.
what stops an unscrupulous person from spamming it and making it unusable to everyone else
Te short answer is: The Laws of Physics.
It is possible to jam a few frequencies here and there, but to jam shortwave transmissions world-wide takes something with the power of a solar flare. That's a lot more than a few hundred megawatts.
During the cold war the Soviet Union + Warsaw Pact tried (and mostly failed) to jam transmissions like the Voice of America, Deutsche Welle, KOL Israel, Radio Tirana and the BBC to their own populations. Estimates were that they were spending about $1 billion per year, had 200 large scale jamming stations and were putting out about 1 terawatt of EMR.