Solve : Whatever Happened to Shortwave Radio??

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The link below is four years ago.

Whatever Happened to Shortwave Radio?

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As recently as 25 years ago, shortwave radio was a preferred source of breaking international news in North America.
Most hours of the day, the BBC World Service boomed in, especially at night on 6175 kHz. There was also Radio Moscow — once the mouthpiece of old-style Soviet propaganda — the Voice of America, Radio Netherlands, Deutsche Welle from West Germany and Radio Berlin International from East Germany.
If you wanted to know what was HAPPENING in Cuba, Tel Aviv or what was then called Bombay, you could tune to Radio Havana, Kol Yisrael or All India Radio directly. -

That is from www.radioworld.com, a web site that still is there.

This last year I cam across my old pocket shortwave radio and tried it for a few minutes. Find something in der 19 mete band. Forgot what it was. So I logged about five minutes of SWL this past year.

Is there anybody here that ever listens to short wave?

Traditional AM shortwave broadcast radio is old technology: the transmitting power levels range from 50 kW to multiples of 1,000 kW (one million watts); this is one area where vacuum tubes still rule. A big one might have an anode ("plate") dissipation of 2,500 kW at an anode voltage of 25 to 30 kV, and around 15 V 640 A for the filament, and weigh around 150 pounds. Such tubes need big and complex cooling plants and very beefy power supplies. The tubes cost upwards of $50,000 and the cooling and PSU equipment is costly, specialized and needs a LOT of careful maintenance by trained personnel. Most shortwave stations still operating are using equipment installed 30 or more years ago and I think they are mostly not being replaced when major work and expenditure is needed.

There is a new digital system called Digital Radio Mondiale (DRM - not to be confused with Digital Rights Management) which allows SW station operators to re-use some of the equipment they have, e.g. antennas (these are also big and expensive) etc and transmit at up to 80% less power (cheaper replacement costs of Tx equipment) for the same global coverage with mono FM radio quality. An international standard is in place. A number of SW broadcasters have switched over to DRM already, and now that All India Radio has taken up DRM you can expect cheap receivers to be available soon. At the moment many people get DRM broadcasts using a communications receiver with 455 kHz out linked to a card in a PC but sets like the Chengdu DR111 are available now at around $180, although personally I would wait for models with better tuning controls.



Articles here

http://en.wikipedia.org/wiki/Digital_Radio_Mondiale

http://www.drm.org/?p=966

http://blog.dxinginfo.com/2012/08/reviews-of-dr111-drm-radio-from-chengdu.html



I have a shortwave radio that I bought from Radio Shack like 15 years ago. I rarely ever use it. I use to have a old Norelco Tube Set that was a shortwave radio. That unit picked up some good range. Russia, Hong Kong, PuertoRico, and of course the common BBC news that I listed to frequently back when i use to listen at night for the best distance picked up with the night just right in a clear night to catch a bounce that is very distant which would come in and fade out. Also sun spot solar flare activity would kill the range due to the ionosphere bombarded with electromagnetic radiation. Location used with short wave radio is New Hampshire, USA.

Strangest transmission picked up was almost 20 years ago, sounded like south america where someone was just saying numbers in spanish. Knowing some spanish i wrote down the numbers and tried to figure out what it was. I figured it was a CODED message since the numbers had no other meaning that made any sense. For all i know it could have been a coded message broadcast of drug cartels etc..LOLQuote from: DaveLembke on September 07, 2014, 10:11:41 AM

a coded message

Many governments OPERATE so-called "numbers stations", including the US. They are well known to short wave listeners. In 2001 the US Govt arrested the Cuban Five who were controlled by messages from a Cuban numbers station.

http://en.wikipedia.org/wiki/Numbers_station

I can remember the "Woodpecker" trasnmissions from the 1970s onwards which are now publicly known to be an over-the-horizon radar system called Duga-3 by its Soviet owners and Steelyard by NATO.



I have fairly recently started getting into listening to shortwave radio. I use what is known as a SDR (Software Defined Radio) which is a USB radio device where a lot of the functionality has been implemented in software. You can almost think of an SDR as an interface between an antenna and a computer. This makes them cheap and pretty verstatile. This is the one I have which is marketed as a TV tuner but can be used as an SDR with special software (I used SDR#) - http://www.amazon.com/Receiver-Previously-Compatible-Packages-Guaranteed/dp/B009U7WZCA/ref=sr_1_2?ie=UTF8&qid=1410109116&sr=8-2&keywords=sdr. This has a range of around 37MHz to 1.2GHz so I then use an upconverter (http://www.amazon.com/Ham-It-v1-2-Upconverter-Converter/dp/B009LQT3G6/ref=sr_1_3?ie=UTF8&qid=1410109116&sr=8-3&keywords=sdr) to pick up shortwave.

This is my current setup (USB stick is the SDR, PCB is the upconverter, battery powers my active antenna which is up in the attic (Must use a battery as a regular switch mode power supply produces far too much noise) and the little box with the label on it injects the power from the battery into the coax that runs to the antenna):


It's a very fun device to play with and is very verstatile since it can monitor a couple of MHz at one time, you can even record parts of the spectrum and then tune to different frequencies in the recording afterwards.

The extremely cool thing with SDRs being able to capture large parts of the spectrum at the same time is that multiple users can listen to them at once. This have GIVEN rise to "WebSDRs" such as this one here: http://websdr.ewi.utwente.nl:8901/ which you can go to and use straight away in your browser. I'd certainly recommend having a play with this to see what you can find. What you can receive will vary based on the time of day but you should be able to pick up "The Buzzer" (http://en.wikipedia.org/wiki/UVB-76) fairly easily on 4625kHz.

This is a screenshot from the SDR software I use (SDR#):

The "waterfall" diagram shows all the different frequencies that the SDR is currently sampling and the brighter colours represent signals of some form, you can then easily zoom in and tune to different frequencies.

The other benefit with it being connected to a computer is that you can use drivers to route the audio signal back into different software allowing decoding of digital signals such as RTTY, Weather Fax and SSTV.

Quote from: DaveLembke on September 07, 2014, 10:11:41 AM

Strangest transmission picked up was almost 20 years ago, sounded like south america where someone was just saying numbers in spanish.

Ahh yes, the "numbers stations" - These were one of the main things that made me buy the SDR setup in the first place, they are pretty interesting. The most common theory is that the numbers are decoded using a "one time pad". Since it is just radio waves being broadcast, it is impossible to track down a potential spy listening to it. A good source of information on these is http://priyom.org/ which has a schedule of when they broadcast as well as information about and recordings of existing stations.camerongray,
Thank you. Excellent post.
I had no idea about SDR and how many companies offer it.
http://en.wikipedia.org/wiki/List_of_software-defined_radios
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List of software-defined radios
From Wikipedia, the free encyclopedia
This article provides a list of commercially available software-defined radio receivers.

Many are rather pricy, but some less than $200.
Thanks for the info on number-stations, as well as Camerons setup looks sweet. It reminds me of that movie called "The Arrival" with charlie sheen http://www.youtube.com/watch?v=GOc01_Ty1eQ One of my favorite sci-fi movies of the 90s, and yes I have it on blu-ray