Vectronics VEC-102K - Manual (Page 31)

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Note: If a DC voltage other than 9 volts is used, readjustment of trimmer C5 will be
required for correct frequency indications.
Setting Up a Useful Shortwave Antenna
The reason why we provided a "universal binding post'' antenna connector (plus separate
ground connector) is to make it as easy and economical for you as possible to try out
different antenna setups. By "universal,'' we mean that you can insert a "banana''-style
plug or make various styles of connection with a simple bare wire.
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 apartment complexes, condos, 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 such as a gutter, fence, flagpole or metal roof. In fact, radio hams and
serious SWL's have experimented with thousands of imaginative antenna ideas.
VERY IMPORTANT: 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.
Note: Stranded copper wire is normally used for making antennas. It may be bare or
covered with plastic insulation. "Bell wire" available in any hardware store is
perfectly suitable.
Your Receiver's Audio Circuit
Many ways to listen in!
The LM386 audio amplifier IC circuit is designed to provide ample volume to not one but
two headphone jacks. We used stereo jacks because today's economical personal music
headphones are as inexpensive as were the bulky "basic headphones'' of yesteryear. Your
receiver provides two headphone jacks to make it very easy for two people to listen
together.