Kenwood TM-451A - Manual (Page 35)

RECEIVING
SWITCHING POWER ON/OFF
Switch ON the DC power supply, then press [PWR] to
switch ON the transceiver.
• If operating mobile, simply press [PWR] on the
transceiver.
• After the on message, the frequency and
possibly other indicators appear on the Display.
To switch OFF the transceiver, press [PWR] again.
In a fixed installation, after the transceiver has been
switched ON, it can then be switched OFF or ON by
using only the power switch on the DC power supply.
VOLUME ADJUST
Turn the VOL control clockwise to increase the audio
level, and counterclockwise to decrease the level.
SQUELCH ADJUST
The purpose of squelch is to silence audio output from
the speaker when no signals are present. When squelch
is set correctly, you will hear sound only while a station
is actually being received. At this time, "BUSY" appears
on the Display.
■ Noise Squelch
Turn the SQL control clockwise to just eliminate the
background noise when no signal is present.
The point at which ambient noise on a frequency just
disappears, called the squelch threshold, depends on
the frequency. Setting the squelch threshold too high
causes squelch to remain closed while a weak signal
is present. The station will not be heard. You may
mistakenly think your transceiver’s receive sensitivity
is low or you have an audio problem.* Setting the
threshold too low allows noise to be heard between
transmissions from other stations.
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