Yaesu FT-950, Руководство по эксплуатации, Страница: 53 / 132

Page 51 FT-950 O
PERATING
M
ANUAL
I
NTERFERENCE
R
EJECTION
IF NOTCH F
ILTER
O
PERATION
(
SSB/CW/RTTY/PKT/AM M
ODES
)
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.
1. Press the [ NOTCH
] button to activate the Notch filter.
The LED inside the [ NOTCH
] button glows orange
and the current “null” position of the NOTCH filter
will appear in the NOTCH indicator on the display.
The [
SELECT
] knob functions as the Notch adjust-
ment knob.
2. Rotate the [ SELECT
] knob to adjust the “null” posi-
tion of the Notch filter.
3. Press the [ CLEAR
] button to move the “null” position
to center.
4. To cancel the NOTCH filter, press the [ SELECT
] knob
momentarily. The graphic disappears from the NOTCH
indicator on the display, confirming that the NOTCH
filter is no longer operation.
A
DVICE
:
Press the [ SELECT
] knob (momentarily) once more,
the NOTCH filter is activated again.
A
DVICE
:
ˆ The IF NOTCH Filter selection will be memorized
independently on each VFO stack of VFO-A and VFO-
B.
ˆ When the optional DMU-2000 Data Management Unit
is connected, the effect of the IF NOTCH filter may be
observed on the Audio Scope (on the “Oscilloscope”
page). The Notch will be observed as a “dip” in the
noise platform observed. What’s more, the “Waterfall”
display may be used to observe the effect of the IF
NOTCH filter, which will appear as a white area in the
colored background area.
[NOTCH] Button
[SELECT] Knob
NOTCH Indicator
[CLEAR] Button
The performance of the IF NOTCH filter is shown
in Figure “
A ”, where the effect of rotation of the
[
SELECT
(
NOTCH
)] knob is depicted. In Figure
“
B
” you can see the notching effect of the IF
N O T C H f i l t e r a s y o u r o t a t e t h e
[
SELECT
(
NOTCH
)] knob to eliminate the incom-
ing interference.
IF
BANDWIDTH
QRM
(Heterodyne)
QRM
(Heterodyne)
IF
BANDWIDTH
Desired Signal Desired Signal
A B