Configuring The Rx Filter; Selecting A Roofing Filter; Switching The If Filter Shape; Switching The Af Filter Type - Kenwood TS-890S Instruction Manual

6 REJECTING INTERFERENCE

Configuring the RX Filter

The steps to configure the settings for the different types of RX
filters are as follows.

Selecting a Roofing Filter

A roofing filter helps to reduce strong interference signals that are
next to the target signal.
1 Press and hold [IF FIL] to display the RX Filter
screen.
.
2 Press [IF FIL] or F2 [FILTER] to select an RX filter
(FIL-A/B/C).
3 Press F3 [ROOF].
Pressing F3 [ROOF] each time switches the passband width.
Setting Value Auto (default)/ 270/ 500/ 2.7 k/ 6 k/ 15 k [Hz]
Auto: A roofing filter with a bandwidth wider than the passband
width of the DSP filter is automatically selected using high
cutoff/low cutoff or Width/Shift. (If there are 2 or more
bandwidths that satisfy the conditions, the narrower one is
selected.)
• In the AM mode, a 6 kHz roofing filter is automatically
selected if the high cutoff frequency is 3 kHz or lower, and a
15 kHz roofing filter is selected if the high cutoff frequency
is higher than 3 kHz.
• In the FM mode, the option is fixed at 15 kHz and cannot be
changed.
• 270 Hz is available for selection when the optional
YG-82CN-1 is attached.
• Pressing and holding F3 [ROOF] each time switches the
options in the reverse sequence.
• The passband width can also be altered by turning the
[MULTI/CH] control.
• "RFT:xxxx" is displayed at the bottom right of the filter scope.
[xxxx:270/ 500/ 2.7k/ 6k/ 15k]
4 Press and hold [IF FIL] or press [ESC] to end the
process.
The IF passband width for the AM mode is twice the
●
value of the high cutoff frequency.
Example: If the frequency is 3,000 Hz, the IF passband
width will be 6 kHz.
6-2

Switching the IF Filter Shape

3 types of IF filter shapes are available for selection according to
the condition of interference and operation.
1 Press and hold [IF FIL] to display the RX Filter
screen.
.
2 Press [IF FIL] or F2 [FILTER] to select an RX filter.
3 Press F4 [IF].
Pressing F4 [IF] each time switches the shape of the filter.
Setting Value Medium (default)/ Soft/ Sharp
• Pressing and holding F4 [IF] each time switches the options
in the reverse sequence.
• The filter shape can also be altered by turning the
[MULTI/CH] control.
• The IF filter option is displayed as "-" and cannot be altered
in the FM mode.
4 Press and hold [IF FIL] or press [ESC] to end the
process.

Switching the AF Filter Type

3 types of audio frequency passbands are available for selection.
1 Press and hold [IF FIL] to display the RX Filter
screen.
.
2 Press [IF FIL] or F2 [FILTER] to select an RX filter.
3 Press F5 [AF].
Pressing F5 [AF] each time switches the shape of the IF filter.
Setting Value Medium (default)/ Wide/ Narrow
• Pressing and holding F5 [AF] each time switches the
options in the reverse sequence.
4 Press and hold [IF FIL] or press [ESC] to end the
process.