THE BEGINNER'S GUIDE TO SHORTWAVE LISTENING 
Bob Grove, Publisher, Monitoring Times

 

Planning your Antenna

 

Any length of wire will pick up signals, but a well-planned antenna installation will pick them up better. For shortwave reception, antenna efficiency and impedance matching are not as important as directivity and noise immunity. That's because the "better" the shortwave antenna, the better it picks up both signals and noise--and there's plenty of noise on shortwave! Directivity favors the signal direction, while noise immunity rejects the interference. 

The maximum signal pickup comes when the horizontal antenna wire is broadside to the arriving signal(s); if the desired signals are from the east, the wire should run north and south. To determine the optimum signal direction for your antenna, acquire a world globe and stretch a string between you and the signal source. The best orientation would be when the string (and your wire antenna) are broadside to the direction of the arriving signal. 

Modern, sensitive, shortwave receivers do not need more than 20-40 feet of antenna, and it can be thick or thin, stranded or solid, insulated or uninsulated. Choose the wire for strength, flexibility and solderability. Try to get it at least 15-20 feet above the ground and as far as possible from electrical power lines (NEVER run it over a power line!); it should also be away from large metallic surfaces like sheet metal roofing, metalized foil insulation, and aluminum siding. 

The simplest antenna is hard to beat--it's a dipole, a horizontal wire broken at or near the center by an insulator, and the two sides connected respectively to the center conductor and a shield of a coaxial cable which runs to your radio. You may even attach the center conductor of the coax to the near end of an unbroken wire antenna, ignoring the coax shield; but at the radio, both the center conductor and the shield (ground) must be connected to the radio for local electrical interference reduction. 

When an outdoor antenna is impossible to erect, mount it in a high indoor area like an attic crawl space, although you may have to tolerate electrical interference from household appliances and computerized equipment. Keep it away from nearby wiring. 

Active antennas are simply short elements connected to high-gain amplifiers and, as such, require power, have electronic parts that may fail, are vulnerable to strong signal overload and static burnout, may add noise (hiss) to the signal, and are more costly than a wire antenna. The better ones, however, are a good substitute when an adequate passive antenna is not an option.

 

Tuning In

 

Spinning the tuning dial through the frequency range of your receiver is lot like shooting in the dark; you may hit something, but you never known what it might be! A good program schedule is essential. Two comprehensive listening guides are published annually, Passport to World Band Radio and the World Radio TV Handbook, but for current English language schedules, you need the most authoritative monthly publication available: Monitoring Times. All three of these publications are available from Grove Enterprises (toll-free 1-800-438-8155). 

Just because a station is listed doesn't mean you will hear it. factors affecting reception include signal propagation conditions, changes in the station's schedule, "beaming" (pattern direction) selected by the station, transmitter power, distance, interference from other close-frequency signals, and your receiving antenna and equipment. 

Although English is the official second language for the majority of foreign stations, this doesn't mean they've chosen it for the time you might be listening. Some countries use shortwave for outreach to their own nationals. 

In general, listening below 10 MHz is best at night, while above 10 MHz is best during daytime.

 

Megahertz, Kilohertz or Meters?

 

With modern tuning accuracy and precision, radio signals are identified by their frequency rather than wavelength, although broadcasters still refer to the time-worn "meter band" as a swath of spectrum where they will be heard. The conversion is simple: to change meters to megahertz (or vice versa), simply divide either into 300. For example, 75 meters is equivalent to 4 MHz (300 divided by 75 is 4, and 300 divided by 4 is 75). 

To avoid dealing with unwieldy numbers, we choose megahertz (million hertz) or kilohertz (thousand hertz); thus, there are 1000 kilohertz in 1 megahertz, a movement of 3 decimal places. For example, 11,850 kHz is the same as 11.850 MHz. To make it even easier, just replace the comma in kHz with a period to make it MHz, or replace the period in MHz with a comma to make it kHz!

 

What Time is it?

 

There are 24 time zones (meridians) around the earth corresponding to the 24 hours of the day. It all starts at 0000 Universal Coordinated Time, or UTC (formerly Greenwich Mean Time, or GMT). When it's 12:00 noon in Greenwich, England, it's still only 7:00 a.m. EST (0700), 6:00 a.m. CST (0600), 5:00 a.m. MST (0500), and 4:00 a.m. PST (0400). Of course as clocks are set ahead an hour during summer daylight savings time, the time difference is an hour less than shown here.  

To change your local time to UTC, simply convert your time to 24 hour time (noon is 1200, 1:00 p.m. is 1300, 11:00 p.m. is 2300) and add the number of hours difference between you and Greenwich. To change UTC to your local time, reverse the procedure: subtract the hours difference between you and Greenwich for your 24 hour local time; then, if it's above 1200, subtract 1200 to get your local time.

 

Utilities versus Broadcasters

 

Virtually all radio transmissions are classified into two groups, broadcasting and utilities. Broadcasters intend their one-way radio transmissions to be heard by a wide audience; utilities are everything else, most notably the two-way communicators. 

Broadcasters still use the venerable amplitude modulation (AM) mode of transmission; nearly all other signals on the air can be monitored in one of two single-sideband modes, upper sideband (USB; the majority) or lower sideband (LSB). 

Always read the instructions which accompany your equipment and accessories; most complaints are the result of failure to read the instructions.