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1. This unit is designed to operate on 12-volts DC, negative ground electrical system
only. Do not attempt to install this unit in a vehicle having a positive ground system.
2. You should not touch the high-polished playback head with any metallic or magnetic
tools.
3. Your unit has built-in filtering to eliminate most of the noise that might come through
the power source. However with some vehicles, particularly older models, some
clicking or other unwanted noise might be present.
CAUTION
IGNITION AND INTERFERENCE NOISE
The most common source of noise in reception is the ignition system. This is normally
due to the face that radio is placed relatively close to the ignition system (engine). This
type of noise can be easily detected because it will vary in intensity of pitch with the
speed of the engine.
Ignition
Usually the ignition noise can be suppressed considerably by using a radio suppression
type high voltage ignition wire and suppressor resistor in the ignition system. (most
vehicles employ this wire and resistor but it may be necessary to check them for correct
operation.) Another method of suppression is the use of additional noise suppressors.
There can be obtained from most CB/ Amateur radio or electronic supply shops.
Radio reception in a moving environment (automobile ) is very different from reception
in a stationary (home). It is very important to understand the difference.
Interference
AM reception will deteriorate when passing through a tunnel or when passing under
high voltage lines. Also, noise can be picked up from passing automobiles. Although
AM is subject to environmental noise, it has the ability to be received at great distance.
This is due to the fact that broadcasting signals follow the curvature of the earth and
are reflected back by the upper atmosphere .
FM reception is just the opposite of AM, It is not subject to environmental noise and it
does not have the ability to be received at great distances (usually 30 miles). Also, the
FM signal can be blocked by tall buildings, mountains, or hills.
To reduce the possibility of these problems, ALWAYS FINE TUNE a station, and if
possible, set the antenna height to 30 inches.
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