Icom IC-7100 Instruction Manual page 9

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1
PANEL DESCRIPTION
Front panel (Controller) (Continued)
PWR
AF
CLR
M-CH
PBT
!5 PREAMP•ATTENUATOR KEY
❍ PREAMP KEY Operation (p. 71)
(Frequency band: HF/50 MHz)
Push to select one of two receive RF preampli-
fi ers, or to bypass them.
• "P. AMP1" is a wide dynamic range preamplifi er. It is
most effective for the 1.8 to 21 MHz bands.
• "P. AMP2" is a high-gain preamplifi er. It is most effec-
tive for the 24 to 50 MHz bands.
• No indicator appears when the preamplifi ers are not
selected.
✔ What is the preamplifi er?
The preamplifi er amplifi es signals in the front end
to improve the S/N ratio and sensitivity. Select "P.
AMP1" or "P. AMP2" when receiving weak sig-
nals.
(Frequency band: 144/430 MHz)
Push to turn the preamplifi er ON or OFF.
• "P.AMP" appears when the preamplifi er is ON.
❍ ATTENUATOR KEY Operation (p. 71)
➥ Hold down for 1 second to turn ON the attenu-
ator.
• "ATT" appears when the attenuator is ON.
➥ Push to turn OFF the attenuator.
• "ATT" disappears.
✔ What is the attenuator?
The attenuator prevents a desired signal from be-
ing distorted when very strong signals are near it,
or when very strong electromagnetic fi elds, such
as from a broadcasting station, are near your lo-
cation.
RF/SQL
TX / RX
BANK
RIT
RIT MENU NB NR
TUNER/CALL MIC/RF PWR SPEED/PITCH P.AMP ATT
!5
P.AMP
ATT
i7100
NOTCH SET AUTO TUNE RX ➔ CS SPEECH
DR QUICK XFC MPAD
!6
!6 NOTCH SWITCH
(Mode = Auto notch:
Manual notch: SSB/CW/RTTY/AM)
➥ In the SSB and AM modes, push to toggle the
notch function between auto, manual and OFF.
• Either the Auto or Manual notch function can be turned
OFF in the "[NOTCH] Switch (SSB)/(AM)" items of the
"Function" Set mode. (p. 36)
SET > Function > [NOTCH] Switch (SSB)
SET > Function > [NOTCH] Switch (AM)
➥ In
FM mode, push to turn the Auto Notch func-
the
tion ON or OFF.
➥ In
CW or RTTY mode, push to turn the Manual
the
Notch function ON or OFF.
• "MN" appears when the Manual Notch function is
ON.
• "AN" appears when the Auto Notch function is ON.
• No indicator appears when the notch fi lter is OFF.
➥ Hold down for 1 second to display the "NOTCH"
screen.
Push to return to the previous screen.
• Rotate the Dial to adjust the notch frequency to reject
an interfering signal while the manual function is ON.
• Notch fi lter center frequency:
SSB/RTTY: –1040 Hz to +4040 Hz
CW: CW pitch frequency –2540 Hz to
CW pitch frequency +2540 Hz
AM: –5060 Hz to +5100 Hz
✔ What is the notch fi lter?
The notch fi lter is a narrow fi lter that eliminates un-
wanted CW or AM carrier tones, while preserving
the desired voice signal. The DSP circuit automati-
cally adjusts the notch frequency to effectively elimi-
nate unwanted tones.
1-5
(p. 77)
NOTCH
SSB/AM/FM