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PORTABLE SHORTWAVE RECEIVERS What to buy and why!
If you only listen to the stronger international broadcast stations, general shortwave listening including the Amateur Bands or if you plan to take a simple receiver with you everywhere, then consider sets in this category. To avoid disappointment, make a note of the following: These receivers give good and cheerful performance, but you must not expect too much. Their size and weight is a given consideration, but that should not be the only factor to consider: FACTS TO PONDER! Some sets only offer PARTIAL coverage of the shortwave bands. If you plan to buy such a set to listen to (a) particular station(s), then check in advance that the set will cover the frequencies you want to listen to. On some receivers the band coverage is incomplete and some bands are missing altogether. Check out the frequency table under Coverage below. This is already a serious disadvantage. LOOK FOR CONTINUOUS TUNING OF ALL BANDS OF INTEREST BETWEEN ABOUT 2.3MHZ AND 30 MHZ! Ease of tuning is another factor to consider! The shortwave bands are extremely crowded and, due to the price range, the shortwave bands may be cramped into a few millimetres on the dial. The sets listed here are better than average in this respect, but if you find the job of searching for stations difficult, go for a set that offers "digital readout". This means the set displays the frequency it is tuned to, rather like a digital clock. This eliminates most of the "guesswork" as to where you are in the band. This is rather more difficult with the conventional "point-and-dial" system. SOME radios do not have the facility for single-sideband (SSB ) reception, so you can't listen to amateur radio operators, radio teletype stations, morse code or utility services. Selectivity (i.e. the ability to separate the station you want from the interference) and dynamic range (see later notes for an explanation of this term) are NOT good enough for picking out very weak stations. Some receivers offer the Phase Lock Loop (PLL) tuning systems. This means the set is generally more stable and easier to tune than receivers using older techniques (such as Wadley Loop). Sets offering FM (VHF) coverage, portability, built-in clocks, and stereo adaptors for FM performance just add to their price without offering better shortwave reception. Points to consider Buy the best possible receiver you can afford. You CANNOT expect $2000 performance from a $200 receiver. You may be disappointed in the results of an inferior receiver. Before assuming your present receiver is useless, or that it needs upgrading, check your antenna facilities. Do not always assume that a long (10 metres or more) random wire antenna in the garden will work wonders. If your receiver is a portable, you may find that such an antenna will cause too much signal to be fed into the receiver's sensitive circuitry. This results in overloading and the appearance of strange stations on odd parts of the dial. For further information, look at the shortwave antenna page on this web site. NEVER expect that by buying an expensive receiver you will be able to tune in exotic countries with hi-fidelity reception. Shortwave signals have to travel vast distances. The imperfections of the ionosphere that forms part of the signal path lead to fading and distortion. As yet, there is NO SUCH THING AS A "SUPER POWERFUL" receiver that pulls rare stations in with "local" quality. It is far better to start with an inexpensive set, learn about the shortwave bands, propagation and the limitations of your receiver. If you decide that international radio listening is interesting enough to start pursuing weaker signals, upgrading is always possible later. NEVER let salesmanship at your local store talk you into buying a receiver without at least a demonstration. There is still a serious problem when it comes to getting advice from shop assistants, many of whom are not aware of the existence of shortwave broadcasting stations. Their main expertise is in video or hi-fi. If the salesman (or -woman) cannot name a major international broadcasting station you can hear on the set, or fails to give a convincing explanation of terms like SSB, the chances are s/he is bluffing! NEVER buy a receiver in the hope that you can buy extra parts at a later stage to upgrade its performance. Some more expensive receivers can have modifications done, but these are the exception rather than the rule. You CANNOT economically make a professional receiver from a US $150 dollar portable! AVOID using the receiver on batteries if there is an option of AC mains electricity. Batteries are up to 1000 times more expensive per unit of electricity than the household current supply. Abbreviations and terms used kHz: kilohertz, MHz: Megahertz, GHz: Gigahertz 1 GHz = 1000 MHz = 1,000,000 kHz. Wavelength (in metres) = 300 divided by Frequency (in MHz) In North America, the medium wave band is usually referred to the "broadcast band" or the "AM band". Weight: This is given in grams (1 oz = 28 grams). Unless stated, this weight is WITHOUT batteries! AM: Amplitude Modulation (i.e. the type of signals found on long, medium, or shortwave). MW: Medium Wave LW: Long Wave SW: Short Wave VHF: Very High Frequency. This term, prominent in Britain, is now being phased out. FM: Frequency Modulation (i.e. mostly found on the section of the dial between 88 and 108 MHz.) Sets made in Eastern Europe, including Russia and for the Japanese market often have a different FM frequency coverage. NBFM: Narrow band FM (This does NOT imply that the set can pick up the FM range between 76 and 108 MHz). This mode is used by amateur radio operators on 10 metre ham band, and in VHF/UHF portions of the spectrum. Some 27 MHz CB operators in Europe also use this mode. You cannot use a narrow band FM position to listen to conventional FM broadcasts - there is too much distortion. AGC: Automatic Gain Control BFO: Beat Frequency Oscillator (needed for SSB reception) FET: Field Effect Transistor IF: Intermediate Frequency IC: Integrated Circuit LCD: Liquid Crystal Display LED: Light emitting diode display Mains: Set can be powered from household AC power supply. PLL: Phase Lock Loop SSB: Single Sideband ( A must for listening to Amateur radio operators on most "Ham" bands Keyboard Tuning: The set has a calculator style pad on the front panel. If you want to tune in 6165 kHz, you simply press the keys 6 1 6 5, and possibly an "EXECUTE" button. The set will then automatically tune to that frequency. This is very handy when moving about the dial fast, and also simplifies tuning for the non-technically minded. Coverage: A receiver that only tunes the "official" shortwave bands may be very limiting. The "Radio Regulations" of the International Telecommunications Union define the shortwave broadcast bands. At the 1992 World Administrative Radio Conference, new bands were created and existing bands were expanded. The band limits in the following table reflect the WARC-92 agreements and broadcast band expansions used on a non-interfering basis (e.g., the 41 mb starting at 6890 kHz on a non-interference basis): Metre
Band Frequencies kHz
Although the allocations do
not become official until 2007, in practice many stations have
already started using the expanded portions under the motto "use it
or lose it." Additionally, there are a few stations that broadcast
outside the band edges above, e.g., Iran on 9022 and a number of
African stations around 9200 kHz. Clearly, receivers with continuous
coverage between 1.6 and 30 MHz are preferred. The bestselling directory of global broadcasting on LW, MW, SW and FM. National and International broadcast and broadcasters Clandestine and other target broadcasters MW and SW frequency listings Terrestrial TV by country Extensive Reference section plus lots more! More excellent radio and shortwave reference books from Amazon.com below BACK TO SHORTWAVE
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