Radio Shack TRC-446 - Manual (Page 17)

17
MAXIMUM RANGE
The maximum range and quality of CB
transmissions vary depending on the fol-
lowing typical conditions:
• The type and quality of antenna
used.
• The height of the antenna's mount-
ing location — the higher the
antenna, the greater the signal's
range
• The surrounding terrain — moun-
tains and tall buildings limit the
range.
• Weather conditions.
• The number of nearby CBs operat-
ing on the same channel.
REDUCING NOISE
The audio clarity enhancer (ACE) circuit
uses compander (compressor and ex-
pander) technology to improve commu-
nication quality. The circuit maintains
the dynamic range while increasing the
signal-to-noise ratio as the gain is auto-
matically controlled according to the in-
put signal level. This results in a
reduction in wide band noise.
The noise blanking (NB) circuit helps
keep background noise to a minimum.
However, strong sources of electrical
noise, generated by spark plugs or the
ignition of your car, or another radio,
might be more than the circuit can com-
pensate for.
If you suspect engine noise as a source,
turn off the engine and operate the CB
with the ignition set to ACC. If most or all
of the noise stops, the problem is in ve-
hicle's ignition or electrical system.
The following few hints can help you re-
duce or eliminate such noise.
• Replace old ignition wires with new,
high-voltage, noise-suppression
wires.
• Install noise suppressors on your
spark plugs, or install new spark
plugs that have built-in suppressors.
• Be sure that the black wire ground
connection is securely attached to
either your vehicle’s battery's nega-
tive (GND) terminal or to a good
electrical chassis ground.
If problems persist, check your alterna-
tor or generator, voltage regulator, and
any stand-alone gauges. Noise from
these sources can be reduced or elimi-
nated using bypass capacitors at vari-
ous output voltage points.
Your local RadioShack store has a wide
selection of noise-suppression accesso-
ries.
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