Now, a few more facts about the ionosphere... This region ranges
about 50 to 500 kilometers (about 30 to 300 miles) above the earth's surface.
Radiation from the sun electrifies the atmospheric gases in this region.
The part of the ionosphere facing the sun will be more strongly electrified
than the part in darkness. Thus the nighttime ionosphere is relatively weakly
electrified as compared to the daytime ionosphere. The ionosphere does not
show the same electrical effects throughout all its levels. For example,
as far as long-distance shortwave broadcasting is concerned, the lowest regions of
the ionosphere bend a shortwave signal very little, but are very absorptive
during daylight hours. This absorption considerably weakens the strength
of a shortwave signal. The higher levels of the ionosphere are generally most
effective in bending back a signal to earth. During the nighttime hours
the lowest (absorptive) layers of the ionosphere dissipate, thus permitting the
shortwave signals to arrive with much greater strength than during daylight
8. What kind of receiver is best to hear shortwave radio?
In general, a shortwave receiver with digital readout and continuous
coverage is best, because you can find stations much more easily by simply
punching in the frequency you want. "Continuous coverage" means the
receiver covers the entire shortwave spectrum from approximately 3 to 30
MHz, with no gaps in coverage. There are still many good analog (i.e.
non-digital readout) receivers available as well, even though you may have
to guess a bit about the exact frequency you're on. In some countries
(particularly in Asia, Africa and Latin America), many of the boom box-type
radios with cassette players often include shortwave bands.
In North America, all Radio Shack stores sell a variety of shortwave
receivers with their own brand name (although often made for them by other
companies). Other electronic stores such as Best Buy, Circuit City, etc.
sell shortwave radios as well. Some of the best quality name brands
available in North America include Sony, Grundig, Sangean and Panasonic.
Large mail-order businesses specializing in shortwave (such as Universal
Radio in Ohio and Grove Enterprises in North Carolina) have catalogs of
shortwave receivers they sell. You can also try a local amateur radio
store in your area, which may carry shortwave receivers.
Receivers range from $50 or $75 paperback-book-size portables, to tiny $200
pocket-size travel portables, to $500 or $1,000 tabletop radios. There are
even wind-up shortwave receivers that you can take everywhere, because they
require no electricity or batteries to operate. Be leary of some of the
very cheap receivers that cost under $100, although some of them can be
quite adequate for listening to strong stations. Again, always try to get
a radio with digital readout and continuous coverage from 3 to 30 MHz. The
number of "bands" it has is not important.
9. Why do shortwave stations
not sound as loud and clear as local AM and
Well, sometimes they do. But quite often, they don't. The reasons for
this are many. First of all, shortwave signals often have to travel many
hundreds or thousands of miles to reach you. In that distance, they are
affected by various factors. There is a lack of spectrum space which
causes shortwave stations to be frequently packed close together. This
means that there may be interference from another station on an adjacent
frequency, or even on the same frequency beamed to a different part of the
world. Countries like China, Cuba and North Korea still jam certain
shortwave broadcasts that are directed toward them from abroad (in
violation of international conventions), resulting in a grinding sound or
bubbling noise on the channel. Atmospheric noise and static can disturb
shortwave signals more than AM and FM signals. And there's also a
phenomenon called "fading," where a shortwave signal fades up and down (or
in and out) over a period of seconds or minutes, due to ionospheric
But despite these disadvantages, shortwave remains the only medium capable
of direct communication from one country to listeners in another country
without intermediaries (like satellites or cable companies, for example).
That's why when a major event or crisis occurs anywhere in the world -- be
it a war, a natural disaster, a major celebration, etc. -- millions of
people tune in to shortwave stations to hear the news direct from its
source. It is also a unique way to hear about different cultures,
religions and musical traditions straight from their sources. We should
add that new, smaller, inexpensive yet higher-quality shortwave receivers
(often with digital readout) are now available in many markets around the
world, making shortwave radio more accessible to more people, and giving it
a better sound than ever before. And with the advent of digital shortwave
broadcasting likely in the near future, the sound quality will improve
10. How many people listen
The truth is that there are no worldwide surveys to determine the number of
listeners to a particular shortwave station, or to shortwave radio in
general. It would simply be too expensive and time-consuming to undertake
these kinds of surveys.
The number of letters that a station receives is really no accurate
indication of its listenership either, since this is often affected by
factors such as contests, giveaways, the literacy levels in different
countries, listeners' abilities to afford international postage costs,
their propensity to write to radio stations in general, etc.
Some of the larger government-funded shortwave stations like the BBC and the
Voice of America have been able to fund local surveys in certain countries
to determine listenership rates. These weekly listenership figures range
from less than 1% up to 30% or more of the population of a given city or
country, depending on the availability of shortwave receivers and the
availability of alternative programming on local radio stations. Shortwave
listenership is generally higher in countries where the domestic media are
largely government-controlled, or where there is a desire to hear programs
from countries which the domestic media do not provide. The BBC and the
Voice of America have estimated their worldwide audiences at as much as 200
million per week. Not many stations have all of the technical facilities
or the number of languages that these government-funded stations have, but
even if they only have a small percentage of the BBC's and VOA's audiences,
these are still very significant numbers.
11. Why do shortwave stations
change frequencies so often?
First of all, some shortwave stations don't change frequencies. Some
stations use only one frequency, all day and all year long. This means
that their coverage area will vary throughout the day and throughout the
year, since the ionosphere is affected by daily and seasonal conditions on
the sun. (Yes, the sun really affects shortwave "propagation," as we call
To make the best of these changing propagation conditions, many shortwave
stations change frequencies throughout the day (and during different
seasons of the year), in order to maintain the best possible coverage of a
particular target area. They use sophisticated computer programs and
on-the-scene listener monitor reports to determine which is the best
frequency range to use at a particular time of the day to reach a
particular target area. And this frequency range will often vary according
to the different seasons of the year. All of this is designed to give the
listener the best possible reception of the station, although it does at
times make it more of a challenge for the listener to "keep up" with the
12. Where can I get lists
of shortwave stations, frequencies and broadcast
These days, there are a lot of station and frequency lists on the Internet,
as well as e-mail "DX" newsletters outlining changes in frequency and time
schedules for shortwave stations around the world. In printed form, we can
recommend two excellent books that come out annually and are available by
mail order and in good bookstores in North America and elsewhere. In the
United States, check bookstores like Barnes & Noble, Borders, B. Dalton and
Waldenbooks for these two guides. They are the "World Radio TV Handbook"
and "Passport to World Band Radio." Each of these books contains
exhaustive information about shortwave stations around the world, their
frequencies, broadcast schedules, mailing addresses, faxes, e-mail
addresses and much, much more. The main difference is that the bulk of the
material in the World Radio TV Handbook is in country-by-country order,
while most of the material in Passport to World Band Radio is in frequency
order. The WRTH contains more schedules for foreign-language
transmissions, while Passport's emphasis is more on English transmissions
and has a more North American focus. They are both excellent guides and
complement one another very well. But be aware that these are annual
guides, and since shortwave frequencies are changing constantly, there will
always be last-minute changes that are not included in either book. The
WRTH is generally published in January of each year, while Passport comes
out around October or so.
There are also magazines that contain information about shortwave stations.
In North America, look for Popular Communications, Monitoring Times and
sometimes publications at Radio Shack. In England, well-known magazines
include Practical Wireless and Shortwave Magazine. Unfortunately, the
editorial lead times that these magazines require makes it difficult for
them to include up-to-the-minute schedule information. For that, try the
e-mail DX newsletters and Internet sites. Many shortwave stations now have
their own web sites which include frequency and program schedules.
13. Why can't I hear a particular station at the time and frequency that's
listed for them?
Well, there are many possible explanations. First, you may be outside the
station's coverage area. Or the list you are looking at may not have the
correct times and frequencies, as these change frequently. Check to see if
the time listed is local time or UTC (Coordinated Universal Time, which is
the same as GMT). Stations may shift their programming by one hour in the
spring and fall to account for daylight savings time. Some people may try
to pick up a shortwave station using a standard AM/FM radio, which of
course is not possible. Or they may have a cheap shortwave receiver that
does not have continuous coverage, and does not cover the frequency range
that the station transmits on. Certain types of buildings (particularly
concrete and steel structures) tend to shield out radio waves of all types,
so you may have to place your shortwave receiver near a window, or even
attach a piece of copper wire to the antenna and place the wire through a
window and mount it outside the house. Solar storms and other conditions
on the sun may cause a temporary fadeout of shortwave signals on a
particular frequency in your area. And you may even be too close to a
shortwave station to hear it well. Since shortwave signals travel up to
the ionosphere and bounce back down to earth, the distance between the
station's antenna and the first hop back to earth is called a "skip zone,"
and the signal may not be audible in that area. But rest assured that even
if you are not able to hear a station's signal where you are at the moment,
other listeners will be hearing it well in other locations around the
world. This is part of the "magic" of shortwave.
14. Would it be easy to put my own shortwave station on the air?
As mentioned above, most countries do not permit private entities to own
and operate shortwave stations within their territory. But some, like the
United States, do allow this. A lengthy application form must be
submitted, accompanied by many technical studies and plans, programming and
legal qualifications, and an application fee of over US$2,000. It
generally takes several months (sometimes a few years) for the FCC to
evaluate an application, and their final decision may be positive or
negative. A positive response would include the issuance of a construction
permit, giving the applicant 18 months to build the station. After the
station is constructed and tested -- assuming the tests are satisfactory --
permission is granted to begin regular programming. This whole procedure
can take several years to accomplish, and a great deal of money. While it
can sometimes be done for less, an applicant should probably budget at
least $1 million for development of a basic 50,000-watt station with one
antenna, from application to the beginning of regular broadcasts.
Then, of course, there is the question of operating costs, which will be
many thousands of dollars per month. Some religious and other
organizations may be able to subsidize these costs, but those stations
which must be totally self-supporting often face great challenges. It is
extremely difficult to sell spot commercials on shortwave stations, since
there are no audience ratings for such a disperse listenership. This same
lack of audience ratings means that block airtime must also be sold very
inexpensively, and nowadays there are a lot of stations (even religious and
government-owned stations) selling block airtime in order to pay for
themselves. This brings the airtime prices down lower still.
The good news is that the lower cost of shortwave airtime has made it very
affordable for organizations of all types to purchase blocks of time on
privately-owned (and sometimes publicly-owned) shortwave stations to get
their message heard around the world, without having to go to the
tremendous work and expenses involved in setting up their own station
(which would be impossible for most of these entities). Some -- but not
all -- of the member stations of NASB offer airtime for sale to outside
organizations. Feel free to contact each member station for more details
on its programming, sales policies, rates, etc.
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