Kenwood TS-990S - Manual (Page 149)

REJECTING INTERFERENCE 6
6-11
Index Contents
■ Changing the bandwidth of the manual notch filter
Configure Wide or Normal for the stopband width of the
manual notch filter. If Wide is configured for the bandwidth,
the stopband width of the manual notch filter will be
expanded twice as wide as Normal.
1 Press [NCH/SEL] (M) or [NCH/SEL] (S) to enable the
manual notch filter for the selected band.
The manual notch filter for the selected band will be
alternated between enabled and disabled.
2 Press and hold [NCH/SEL] (M) or [NCH/SEL] (S) .
• "Normal" or "Wide" is configured for the passband width.
• If "Wide" is selected, "NOTCH W" will appear above the
frequency display of the selected band, in the main screen.
Auto Notch Filter (SSB)
If there is a single interfering tone (i.e., a cyclic signal
like CW) in the receive bandwidth, the auto notch filter
searches for, finds, and suppresses the interfering tone
automatically.
This function occasionally slightly suppresses the S-meter
readout or the target signal.
If there is a weak interference signal, beat cancellation
may be able to eliminate it more effectively.
Target Signal
Interfering Wave
[F1] [F7]
[ESC] [MULTI/CH]
[A.NCH/SEL] (M) [A.NCH/SEL] (S)
■ Activating the auto notch filter
1 Press [A.NCH/SEL] (M) or [A.NCH/SEL] (S) to enable
the auto notch filter for the selected band.
• The “A.NCH/SEL” (M) or “A.NCH/SEL” (S) LED lights green.
• In the main screen, "A.NOTCH" will appear above the
frequency display of the selected band.
• The auto notch filter for the selected band is deactivated
when the corresponding key is pressed again.
Note:
◆ The auto notch filter is deactivated if the manual notch filter or band
elimination filter is active while the auto notch filter is active.
■ Adjusting the tracking speed of the Auto Notch
Adjust the speed of the notch filter to follow the
interference according to the changing status of the
interfering signal.
1 Press and hold [A.NCH/SEL] (M) to open the Auto
Notch screen.
2 Press [-] (F4) or [+] (F5), or rotate the MULTI/CH
control to select the level for each frequency band.
Available range is "0" (disable the tracking) and from "1"
(slow) to "4" (fast). The default is "2".
3 Press [ESC] to exit.
Pressing and holding [A.NCH/SEL] (M) or [A.NCH/SEL] (S)
closes the Auto Notch screen.