Thursday, February 26, 2009

High-End Receivers for Shortwave Listeners

Serious shortwave listeners, especially those who consider themselves DXers or DX-listeners may use very expensive communications receivers and outdoor antennas. Typically, a modern solid state communications receiver will be of the superheterodyne type in double, triple or, more rarely, quad conversion. It will feature multiple RF and IF amplification stages and may have at least one IF stage that is crystal controlled. It will usually have an additional BFO product detector for SSB and CW reception capabilities. The frequency coverage of receivers of this type is typically in the range of 500 kHz to 30 MHz.

The front panel controls are typically more comprehensive than those on a local broadcast receiver. Usual features include: signal strength meter; RF gain control; AVC/AGC adjustments; antenna tuner; bandwidth filters; BFO tuning; audio limiters or attenuators. Frequency display dials may either be analog (typically marked to fine increments for accuracy) or digital.
Three portable shortwave receivers

The older generation of vacuum tube-based communications receivers are affectionately known as boatanchors for their large size and weight. Such receivers include the Collins R-390 and R-390A, the RCA AR-88, the Racal RA-17L and the Marconi Electra. However, even modern solid-state receivers can be very large and heavy, such as the Plessey PR2250, the Redifon R551 or the Rohde & Schwarz EK070.

Modern medium quality shortwave radio receivers tend to be relatively inexpensive and easily accessible. Many hobbyists use even less-expensive portable receivers with good results. In general, any given shortwave radio will benefit from an external antenna — even a simple wire antenna — as long as the antenna is away from electrical noise sources. The standard shortwave receiving antenna is the dipole antenna which can be readily purchased or made by hand from a roll of wire and a couple of insulators.

(From Wikipedia, published under Gnu Free Documentation License)

Wednesday, February 25, 2009

Shortwave Listening and DXing

There are basically two kinds of shortwave hobbyists. First, there are the shortwave listeners who are interested in listening to interesting broadcasts, news and music from foreign countries. Second, there are DXers who want to receive as many stations as possible from as many different countries as possible. Compared to shortwave listeners, the DXers are often more techincally minded, and they like to build new antenna systems, test new radios and receive the weakest possible signals.

One part of the hobby is traditionally collecting so-called QSL cards from SW broadcasters. The DXers send a written (or email) report of their reception to the radio station and request a confirmation of the reception. For international broadcasters, the reception reports can give valuable information about the real quality of the received signal around the world. Of course, most stations use paid monitors as well.

In the 1980s there were dozens of radio shows that were broadcasted for shortwave enthusiasts. Unfortunately, these shows have nowadays been dropped by many international broadcasters. The shortwave enthusiasts are not anymore considered an important audience for the programming.

It is impossible to know how many shortwave listeners there are around the world, but most estimates place the number in the millions. The shortwaves are, after all, still an important part of broadcasting in the developing countries. For these people, shortwaves are not a part of a hobby. On the contrary, shortwave broadcasting is part of their everyday life.

Wednesday, February 18, 2009

Sangean ATS-909

Sangean ATS-909 is another great portable shortwave radio, which can easily be carried around the world when travelling. But it can equally well be used at home if you don't have much space for any huge communication receiver.

Tuesday, February 17, 2009

Looking for Shortwave Receiver?

If you have not yet a shortwave radio, I suggest you to start with some cheap model. Many traditional manufacturers have been in the business for decades and usually their receivers can be trusted to have decent quality.

I would suggest you to choose from the following manufacturers:

* Sony
* Grundig
* Sangean

All three manufacturers produce shortwave receivers that should provide you good or outstanding performance.

If you are ready to put some more money into your hobby, you might want to see if Ebay has something to offer.

Monday, February 16, 2009

WRTH World Radio and TV Handbook

World Radio and TV Handbook (WRTH) is another useful book for all the shortwave enthusiasts around the world. Unlike Passport to World Band Radio, WRTH includes information about medium wave and FM broadcasters as well. Even TV stations are included in the handbook that has been an important work of reference book for decades. A new edition of the book is published every year.

In addition to the information about broadcasters, frequencies and broadcasting schedules, WRTH reviews both portable shortwave receivers and more expensive communication receivers that are meant for desktop use. Furthermore, even the advertising in the margins of the book provide lots of useful information for anyone who is interested in the world of radio stations around the world.

Buy the WRTH, if you want to know more about broadcasting around the globe!

Tuesday, February 10, 2009

Portable Shortwave Receivers

Today practically all of the cheap portable shortwave receivers are digital. When I started shortwave listening in the 1980's, only the more expensive table top receivers were digital. My fist shortwave receiver was a Soviet portable receiver of model Selena B212. The model is still legendary for its good performance for the price, but it was rather difficult to use without a separate digital frequency counter.

Most beginners should be happy with any portable receiver in the price range between $99-$199. Sangean, Sony and Grundig have produced shortwave receivers of decent quality in this price range. I myself use a Sony ICF7600 and I have been completely happy with its performance. I have very pleasant memories of sitting under a palm tree in the Dominican Republic while listening to icehockey match broadcasted from Scandinavia a few years ago...

The shortwave receivers in this price range usually perform quite well with the in-built whip antenna. If you are interested in listening to more exotic stations with weak signals, you might need an external antenna and/or a better receiver. But for most shortwave listeners it is enough to have a decent portable receiver.

Shortwave broadcast bands

Both Passport to World Band Radio and World Radio and TV Handbook publish schedules of international broadcasters that broadcast in English or in any other language of the world. There are, of course, also free Internet resources that help you to locate interesting shortwave transmissions on the wide spectrum of shortwaves.

It is important to note that only part of the shortwave spectrum is used for broadcasting. Other part of the radio frequencies are used by amateur radio operators and many kinds of utility stations. The following list gives an overview of the frequencies used by broadcasters around the world.

11 meters – 25.67–26.10 MHz – Very few stations are active in this band

13 meters – 21.45–21.85 MHz – This band can be used for long distance reception during the daylight hours

15 meters – 18.90–19.02 MHz – Rarely used.

16 meters – 17.48–17.90 MHz – Good for daytime reception, and seasonally in the night.

19 meters –15.00–15.825 MHz – Day reception good, night reception best during summer

22 meters – 13.57–13.87 MHz – Similar to 19 meters; best in summer.

25 meters – 11.50–12.16 MHz – Generally best during summer; and ideal during the period before and after sunset.

31 meters – 9250–9995 kHz – Good year-round night band for long distances; seasonal during the day, with best reception in winter.

41 meters – 7100–7600 kHz – Reception varies by region – reasonably good night reception, but few transmitters in this band are targeted to North America. Good reception for daytime in Europe.

49 meters – 5800–6300 kHz – Good year-round night band; local daytime reception

60 meters – 4400–5100 kHz – Mostly used locally in tropical regions (Asia, Latin America, Africa, Pacific Area), though usable at night also for long distance reception.

75 meters – 3900–4050 kHz – Mostly used in Eastern Hemisphere including Europe

90 meters – 3200–3400 kHz – Mostly used locally in tropical regions (Asia, South America, Africa)

120 meters – 2300–2495 kHz – Mostly used locally in tropical regions (Asia and South America)