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FT-450D O
PERATION
M
ANUAL
N
OISE
B
LANKER
(
I
NTERFERENCE
R
EJECTION “S
IGNALS
WITHIN
3
KHZ
”
)
The
FT-450D
includes an effective Noise Blanker, which can significantly reduce noise caused by automotive
ignition systems.
IPO/ATT
(
A
DJUST
THE
R
ECEIVING
S
ENSITIVITY
)
You may reduce the receiving signal strength to 20 dB when extremely strong local signals or high noise de-
grade reception. You may optimize the characteristics of the receiver front-end, for best reception, depending on
the noise levels and the signal strengths.
Press the [
IPO/ATT
] button several times to set the
desired selection, per the chart below.
The selection will be indicated in the Block Diagram
on the display.
Block Diagram
[
IPO/ATT
] button
C
ONVENIENCE
F
EATURES
1. Press the [
NB
] button to activate the Noise
Blanker.
2. Press the [
NB
] button again to disable the Noise
Blanker.
The selection will be indicated in the Block Diagram
on the display.
Block Diagram
[
NB
] button
N
OTE
An attenuator is always “ON” between 30kHz
and 1.7MHz.
ATT
:
OFF
,
IPO
:
OFF
Attenuator is OFF, and the incoming
signal is amplified by the RF preampli-
fier.
ATT: OFF, IPO: ON
Attenuator is OFF, and the incoming
signal bypasses the RF preamplifier,
yielding direct feed to the first mixer.
ATT: ON, IPO: OFF
Attenuator is ON, (the incoming signal
is reduced by 20 dB) and the incom-
ing signal is amplified by the RF pream-
plifier.
ATT: ON, IPO: ON
Attenuator is ON, (the incoming signal
power is reduced by 20 dB) and the
incoming signal bypasses the RF
preamplifier, yielding direct feed to the
first mixer.
