June 1959 Popular Electronics
 Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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 "DXing," or long distance communications,
has been a goal of amateur radio operators since the inception of radio. The sport
is as popular today as it was in 1959 when this article appeared in Popular
Electronics magazine. As you might expect, achieving success at making contacts
with
like-minded hobbyists half-way around the world has been made quite a bit easier
both by vastly improved transmitters, receivers, and antennas and by a much greater
knowledge of propagation paths and accommodating atmospheric conditions. In 1959,
you relied on monthly publication of reported conditions that was itself a few months
old. Nowadays a DXer simply visits one of many websites with real-time status on
meteorological status and current operator reports on contact conditions, equipment
being used, frequency and power levels, etc. Still, though, it takes a special kind
of dedication to earn the coveted "Worked All Continents" certificate.
Log All Continents on the Broadcast Band
By Glen H. Kippel W0WPO/WPE0NA
 Medium waves provide real DX'ing challenge
It could be that you, like so many others, feel that world-wide reception can
be had only on the short waves. But with a good receiver and antenna, it is possible
to log all continents on the medium-wave broadcast band.
DX Broadcast Stations Heard in the United States
You may say to yourself, "That's all well and good, but I can't afford a professional
receiver, and I don't have the room for a 500' long-wire." Well, while such equipment
is certainly desirable, less expensive receivers can be utilized successfully. Very
inexpensive D/F (Direction-Finder) receivers, such as the 12-tube MN-26C and the
17-tube BC-433F, can be purchased at many surplus stores and made to work as well
as most communications receivers. This is not so surprising when you consider that
the BC-433 has three r.f. stages.
The "Q-5'er." Older console models usually contain sensitive
chassis, and can be adapted for DX work by the addition of a Q-multiplier, sideband
slicer or "Q-5'er" to increase selectivity. Of course, the accessory must match
the receiver's i.f. frequency.
The surplus BC-453 receiver, long known as the "Lazy Man's Q-5'er," contains
an 85-kc. i.f. which is very sharp. It can be employed with any i.f. frequency commonly
used in broadcast receivers (175, 262, 455 and 456 kc. being the most common) by
breaking the i.f. signal lead in a convenient place, connecting to it a small capacitor
and, from that, a length of coaxial cable to the antenna post on the "Q-5'er."
Audio from the "Q-5'er" can then be taken from a large capacitor connected to
its output stage and fed into the receiver's phono input, if it has one. If it does
not, the lead from the detector to the volume control in the receiver can be cut
and a shielded cable run from the volume control to the "Q-5'er." It may be necessary
to connect a variable resistance in series with this lead to avoid overloading the
receiver audio section.
If desired, the sensitivity and signal-to-noise ratio can be boosted considerably
by connecting a simple preselector (r.f. amplifier) between the antenna and receiver
antenna posts.
Antennas. The higher and longer antennas are much to be preferred,
whether they are of the long-wire or the dipole type. If it is impossible to erect
an antenna more than ten feet high or so, just remember that any antenna is better
than no antenna at all, and concentrate on making the receiver more sensitive.
Since few antennas can be long enough to resonate effectively at broadcast frequencies,
the alternative is to scoop in as much signal as possible. If you can, use stranded
antenna wire, as it has lower signal resistance than solid wire, and use double
insulators to reduce losses in wet weather.
Join a Club. If you have the equipment, you need to know where
and when to listen. To find out what other DX'ers are hearing, the best thing to
do is to join a radio club.
The Newark News Radio Club, 215 Market St., Newark 1, N. J., dedicates a section
of its monthly bulletin to the broadcast band. Another club is the National Radio
Club, c/o Harold F. Wagner, R. D. #1, Lake City, Pa.
The DX'ers' Radio Club, which was formed solely for the purpose of BCB DX'ing,
also issues a monthly bulletin. Information can be had by writing to the DX'ers'
Radio Club, c/o Jim Ernst, 563 Park Ave., Scotch Plains, N. J.
Using the Station List. Stations which are heard well in the
United States, plus some of the better DX stations which are heard regularly, are
listed at right.
As a rule, the European and African stations can be heard from sunset, local
time, until they begin to fade out around sunrise in Europe. You can bring in the
Central and South American stations until they sign off around 0100 EST. The Pacific
Area and the Far East are heard best from around 0300 EST until American stations
sign on and drown out the weaker DX. Stations listed as being in the Caribbean Area
can be heard from about 0410 EST, when they begin signing on. And listeners in western
states will find that some stations in Central America will come in better in the
early morning hours because there will be less local interference.
Winter is the best season for DX, although the early spring is almost as good.
The reason is that the sun's rays strike the ionosphere at more of an angle and
cause less ionization of the atmosphere, resulting in less ionospheric absorption.
The years of low sunspot activity will provide better DX for the same reason.
The next sunspot low will be 1964 to 1966, but there is no reason to wait until
then because solar activity varies considerably even over very short periods.
Posted April 3, 2023
(updated from original post
on 5/17/2017)
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