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4-1
BASIC MANUAL
3
4
4
RECEIVING AND TRANSMITTING
Preamplifiers
144, 430, and 1200 MHz bands
The preamp amplifies received signals in the receiver
front end to improve the signal-to-noise ratio and
sensitivity. A preamp is used when receiving weak
signals.
L
Each band memorizes the Preamplifier setting.
1. Select the operating band.
2. Push
.
•
Opens the FUNCTION screen.
3. Touch [P.AMP/ATT] to turn this function ON or
OFF.
4. To close the FUNCTION screen, push
.
Attenuator
144, 430, and 1200 MHz bands
The Attenuator prevents a desired signal from
becoming distorted when a very strong signal is near
the frequency, or when a very strong electric field,
such as from a broadcasting station, is near your
location.
L
Each band memorizes the Preamplifier setting.
1. Select the operating band.
2. Push
.
•
Opens the FUNCTION screen.
3. Touch [P.AMP/ATT] for 1 second.
L
Touching [P.AMP/ATT] again turns OFF the
Attenuator.
4. To close the FUNCTION screen, push
.
L
If a strong signal is received and “OVF” (Overflow)
is displayed, turn ON the attenuator, or reduce the
RF gain until “OVF” disappears. (p. 3-9)
Displayed when
the Attenuator
is ON.
NOTE:
When you use the preamp while receiving
strong signals, the receiving signal may be distorted.
In such case, turn OFF the preamp.
Displayed when
a preamp is ON.