User's Manual

Page 26 FT-450D OPERATION MANUAL
NOISE BLANKER
(
INTERFERENCE REJECTION “SIGNALS WITHIN 3 KHZ”
)
The FT-450D includes an effective Noise Blanker, which can significantly reduce noise caused by automotive
ignition systems.
IPO/ATT
(
ADJUST THE RECEIVING SENSITIVITY
)
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
CONVENIENCE FEATURES
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
NOTE
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.