Rejecting Interference; Attenuator; Switching The Rx Filter Band Characteristics; Switching The Rx Filter (A, B, C) - Kenwood TS-890S Instruction Manual

6 REJECTING INTERFERENCE

Attenuator

The attenuator is a function for attenuating the RX signals. If there
is interference due to strong signals near the target signal, turning
on the attenuator helps to reduce interference caused by nearby
frequencies.
It is also effective in situations where the RX audio is distorted
when the RX signal is too strong. This transceiver comes with three
different types of attenuators.
Press F [ATT].
Pressing F [ATT] each time switches the attenuation level.
Setting Value Off (default)/ 6 dB/ 12 dB/ 18 dB
• Pressing and holding F [ATT] each time switches the options
in the reverse sequence.
• The attenuation level is stored for each antenna selection
band.
• The status of the attenuator (attenuation level) is displayed
in the key guide.
.

Switching the RX Filter Band Characteristics

Switching the RX Filter (A, B, C)

The setting for the band characteristics of the RX filter on this
transceiver can be switched at one touch according to the
operating status to one of the three types (A, B or C).
• The band characteristics are configured by combining the
roofing filter or IF and AF filter, high cutoff/low cutoff and WIDTH/
SHIFT. A different RX filter setting (A, B or C) can be stored for
each of the SSB, CW, FSK, PSK, FM and AM modes.
Press [IF FIL].
Pressing [IF FIL] each time switches the RX filter in the order
of "A", "B" and "C".
• The selected filter is displayed at the top left of the filter
scope.
The RX filter does not switch to Type C if Menu [6-10] "RX
Filter Numbers" below is configured to "2".

Configuring the Selectable Types of RX Filters

The selectable types of RX filters can be configured to three (A, B
and C) or two (A and B).
Configure in Menu [6-10] "RX Filter Numbers"
Setting Value 2/ 3 (default)
REJECTING INTERFERENCE 6

Filter Scope

The following information is displayed on the filter scope screen.
• Selected RX filter (A, B or C)
• Image of the RX filter passband characteristics (trapezoid)
• Audio spectrum of the RX audio
• Parameters including the IF filter passband width
• Pitch frequency in the CW mode
• Notch point of the notch filter
• Passband width of the roofing filter
.
The audio spectrum is not shown on the filter scope while
●
the audio scope screen is displayed.
The audio spectrum is not shown on the filter scope while
●
the RTTY/PSK communication screen is displayed.
An out-of-range marker
●
image of the passband cannot be displayed within the
display area because the shift amount of the filter in the
CW mode is large.
The audio spectrum is usually displayed within the image
●
of the passband. However, it may be displayed beyond
the image of the passband if there are excessively high
input signals.
When the notch filter is ON, the indicator representing
●
the notch point is displayed in white. The indicator is
displayed in white when the notch point is on the positive
side of the carrier wave in the AM mode. If the notch point
moves towards the minus side of the carrier wave, the
indicator changes to orange and moves from the left
edge of the screen to the right edge.
SSB
CW
FSK
PSK
AM/FM
is displayed when the
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