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5-10
5
FUNCTIONS FOR RECEIVE
■
Preamplifier
The preamp amplifies received signals in the receiver
front end, to improve the S/N ratio and sensitivity. Set
this to preamp 1 or preamp 2 when receiving weak
signals.
➥
Push [P.AMP]
(MF3)
several times to set the
preamp OFF, preamp 1 ON or preamp 2 ON.
➥
Hold down [P.AMP]
(MF3)
for 1 second to turn the
preamp function OFF.
P.AMP
1
For all HF and 50 MHz bands
P.AMP
2
High-gain preamp for 24 MHz band and
above (Available for all HF and 50 MHz
bands)
✔
About the “P.AMP2”
The “P.AMP 2” is a high gain receive amplifier. When
the “P.AMP 2” is used in the presence of strong elec-
tromagnetic fields, distortion sometimes results. In
such cases, use the transceiver with the “P.AMP 1” or
“P.AMP OFF” setting.
The “P.AMP 2” is most effective when:
• Used on bands above 24 MHz and when signals are
weak.
• Receive sensitivity is insufficient when using low-
gain antennas, or while using a narrow band an-
tenna (such as small loop, a Beverage antenna or a
short Yagi antenna).
■
Attenuator
The attenuator prevents a desired signal from being
distorted when very strong signals are near the de-
sired frequency or when very strong electromagnetic
fields, such as from broadcast stations near your lo-
cation.
➥
Push [ATT]
(MF4)
several times to set the attenua-
tor 6 dB, 12 dB, 18 dB or attenuator OFF.
➥
Hold down [ATT]
(MF4)
for 1 second to turn the at-
tenuator function OFF.
P.AMP
ATT
ATT
6dB
6 dB
attenuation
ATT
12dB
12 dB
attenuation
ATT
18dB
18 dB
attenuation
The preamp (P.AMP1 or P.AMP2) cannot be used
while the digital selector is activated.
Also the preamp is automatically disabled when the
digital selector is turned ON.