Setting up a Shortwave Listening Antenna
Your receiver is so sensitive that even a few feet of wire strung
indoors will provide reception of stronger signals, particularly
at night. 20 to 30 feet of wire is much better. Therefore, you
can count on good reception even if you are limited to keeping
the antenna indoors as might be required in apartments, etc.
Stringing all or part of your antenna outdoors is always better.
An ideal antenna for this receiver would consist of 25 to 100
feet of wire outdoors, as high as is safely possible. Such
antennas are called "random long wires" and also work fine in
most attics. (Foil-backed insulation or metal roofing will
reduce the usefulness of an attic as antenna space.)
Your antenna can be horizontal, vertical or a combination of both.
It can be tubing or pipe as well as wire. The wire can be bare
or insulated. It could be something not intended to be an
antenna at all, such as a gutter, fence, flagpole or metal roof.
A shielded coaxial cable feedline to the antenna such as RG59 or
RG59 is NOT essential but may prove helpful in eliminating or
reducing hum or buzz from nearby electrical wiring, especially
when the receiver is operated from a power supply. The coax
shield is connected to the receiver Ground terminal.
Even if not using a coax feedline, a wire from the Ground
terminal to an earth ground rod or cold water plumbing (metal,
NOT plastic) can reduce AC interference and improve reception.
The grounding wire should be as short as possible.
CAUTION:
Use care and common sense when putting up outdoor antennas.
Be certain that your wires or your ladder
cannot come into contact with electrical power lines.
You can be KILLED by accidental contact with Power lines.
IMPORTANT!
All outdoor antennas should include a way to switch the antenna
away from radio equipment to ground during thunderstorms. It
does Nor take a direct lightning hit to damage this receiver or
other equipment. If the receiver remains connected to an
antenna during a storm, lightning strikes a mile away can burn
out parts, particularly transistor Q1 in the 1253 receiver.
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Tuning SSB (Single Sideband) Voice Signals
SSB signals are those voice signals which sound like Donald
Duck unless they are tuned in properly. They have no
background carrier as do AM broadcast signals. On modern ham
radio transceivers, tuning SSB is made so easy by by internal
filters that many licensed ham operators are not aware of the
basic technique for tuning in SSB signals on receivers without
such filters.
The first fact to know about any given group of SSB signals is
whether they are Upper (USB) or Lower (LSB) Sideband. In ham
communication, LSB used on 1.8 through 7.3 MHz, and USB is
used for higher frequency bands (14, 18, 21 , 28 MHz.)
Think to yourself: for LOWER sideband, tune DOWN.
For UPPER sideband, tune UP.
This means you would "approach" the LSB signal by tuning from
higher frequency (right) to lower (left), from higher voice pitch to
lower. Here's how, step by step:
1. Pick out a strong, high-pitched Donald Duck voice.
2. Turn the Fine tuning knob ever so slightly to the left.
3. If the pitch of the voice went DOWN slightly, you're heading
in the right direction.
4. SLOWLY tune left slightly more until the voice is clear.
Reverse this process to tune to UP (to the right) to USB signals
on the bands above 40 meters. The Regeneration control often
can be used to do the last touch of fine tuning to bring the voice
in clearly. If signals are exceptionally strong, it may be
necessary to reduce RF gain.
SSB transmissions also are used by embassies, international
airlines agencies of various governments, so you might find
interesting voice signals on other than ham frequencies. Check
with an experienced Shortwave Listener (SWL) or listings in
popular Communications Magazine (available at newsstands) for
more details.
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