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5
FUNCTIONS FOR RECEIVE
5-2
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Preamplifi er
D
The preamplifi er amplifi es weak signals in the receiver
front end, to improve the S/N ratio and sensitivity.
Turn ON this function when receiving weak signals.
(Frequency band: HF/50 MHz)
➥
Push
P.AMP
ATT
(
C
) one or more times to set the pre-
amp OFF, preamp 1 ON or preamp 2 ON.
•
Either “P.AMP1” or “P.AMP2” is displayed when the pre-
amp 1 or preamp 2 is ON.
•
No icon is displayed when the preamplifi er is OFF.
P.AMP1
Wide dynamic range preamplifi er. It is most
effective for the 1.8 to 21 MHz bands.
P.AMP2
High-gain preamplifi er. It is most effective
for the 24 to 50 MHz bands.
(Frequency band: 144/430 MHz)
➥
Push
P.AMP
ATT
(
C
) turn the Preamplifi er ON or OFF.
• “P.AMP” appears when the preamplifi er is ON.
•
No icon is displayed when it’s OFF.
Attenuator
D
The attenuator prevents a desired signal from being
distorted when very strong signals are near the signal’s
frequency, or when very strong electromagnetic fi elds,
such as from broadcast stations are near your location.
These can both be independently set for each band.
➥
Hold down
P.AMP
ATT
(
C
) for 1 second to turn ON the
Attenuator.
•
“ATT” appears on the display when the Attenuator is ON.
➥
Push
P.AMP
ATT
(
C
) to turn it OFF.
✔
About the “P.AMP2” preamplifi er
Preamp 2 is a high gain receive amplifi er. When it is
used in the presence of strong electromagnetic fi elds,
distortion sometimes results. In such cases, use ei-
ther the “P.AMP1” or “P.AMP OFF” setting.
Preamp 2 is most effective when:
• Used on bands above 24 MHz and when signals are
weak.
• Receive sensitivity is insuffi cient 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).
About the Preamplifi er and Attenuator switching procedure
Push or hold down
P.AMP
ATT
(
C
) to switch the Preamplifi er and Attenuator, as shown below.
Hold down
Push
ATT ON
Push
P.AMP
OFF
P.AMP
ON
Push
ATT ON
P.AMP
OFF
P.AMP1
ON
P.AMP2
ON
P.AMP
ATT
P.AMP
ATT
P.AMP
ATT
Hold down
P.AMP
ATT
P.AMP
ATT
Push
P.AMP
ATT
• HF/50 MHz frequency bands
• 144/430 MHz frequency bands
Preamp and attenuator
P.AMP
ATT
P.AMP
ATT