If Notch Filter Operation (Ssb/Cw/Rtty/Pkt/Am Modes) - Yaesu FT DX 9000MP Operation Manual

IF N F
OTCH ILTER
The IF Notch filter is a highly-effective system that allows you to slice out an interfering beat note or other carrier signal
from inside the receiver passband.
SUB(VFO-B) [NTCH] Knob
SUB(VFO-B) [NTCH] Switch
( VFO-A ) IF N
M B
AIN AND OTCH
1. Press the Main (VFO-A) band [ NOTCH ] switch. The
LED imbedded in the switch will glow Red to con-
firm that the IF Notch filter has been engaged.
2. Rotate the Main (VFO-A) band's [ NOTCH ] knob to
null out the interfering carrier.
To switch the IF Notch filter off, press the Main (VFO-A)
band's [ NOTCH ] switch once more. The LED imbedded
in the switch will turn off, confirming that the IF Notch
filter is no longer operating.
( VFO-B ) IF N
S B
UB AND OTCH
1. Press the Sub (VFO-B) band's [ RX ] switch to en-
gage Dual Receive operation.
2. Press the Sub (VFO-B) band [ NTCH ] switch. The
LED imbedded in the switch will glow Orange to con-
firm that the IF Notch filter has been engaged.
3. Rotate the Sub (VFO-B) band's [ NTCH ] knob to null
out the interfering carrier.
The performance of the IF Notch filter is shown in
Figure (A), where the effect of rotation of the
[ NOTCH ] knob is depicted. In Figure (B) you can
see the notching effect of the IF Notch filter as you
rotate the [ NOTCH ] knob to eliminate the incom-
ing interference.
A
NOTCH
IF BANDWIDTH
FT 9000MP O
DX PERATION
I I I I I
NTERFERENCE NTERFERENCE NTERFERENCE
NTERFERENCE NTERFERENCE
( SSB/CW/RTTY/PKT/AM M
O
PERATION
O
PERATION
O
PERATION
B
Desired Signal
QRM (Heterodyne)
IF BANDWIDTH
M
ANUAL
R R R R R
EJECTION EJECTION EJECTION
EJECTION EJECTION
VDD
To switch the IF Notch filter off, press the Sub (VFO-B)
band's [ NTCH ] switch once more. The LED imbedded in
the switch will turn off, confirming that the IF Notch filter
is no longer operating.
A A A A A
D D D D D VICE VICE VICE
VICE VICE
The Sub band (VFO-B) frequency display will
show the Notch frequency for 3 seconds when-
ever the outer [ NOTCH ] knob is turned.
You may disable this feature (displaying the Notch
frequency) via Menu item "DISPLAY 022
LEVEL INDICATOR." See page 148 for details.
If you have an after-market monitor connected
to the DISPLAY jack, you can use the Audio
Scope display on the "Audio Scope/Oscillo-
scope" page to observe visually the position of
the Notch. Rotation of the [ NOTCH ] control will
produce a change in the notch frequency that
you can see changing position. The "Waterfall"
display capability of the Audio Scope may also
be used for this purpose.
The width of the IF Notch null may be adjusted
using Menu Item "RX DSP 092 IF-NOTCH-
WIDTH". Both "Wide" and "Narrow" selec-
tions are available, with "Narrow" providing the
least disruption of the "desired" signal.
Under the frequency display, you may also use
the Bar Display to show the position of the IF
Notch. Use Menu Item "DISPLAY 016 BAR
DISPLAY SELECT" to engage this function.
N N N N N
O O O O O TE
When the [ NOTCH ] switch is pressed and held in for
two seconds, the center of the notch action will be reset
to the positions described below (mode-sensitive):
SSB/AM: The Notch will center at 1.5 kHz (center
of the receiver passband).
CW: The Notch will center on the frequency
programmed by the [ PITCH ] knob.
(S (S (S (S (S 3 3 3 3 3 ) ) ) ) )
IGN IGN ALS ALS WITHIN WITHIN KHZ KHZ
IGNALS IGN IGN ALS ALS WITHIN WITHIN WITHIN KHZ KHZ KHZ
)
ODES
MAIN(VFO-A) [NOTCH] Knob
BIAS TEMP SWR
MAIN(VFO-A) [NOTCH] Switch
TE TE TE
TE
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