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DNR (Digital Noise Reduction)
The Digital Noise Reduction (DNR) system is de-
signed to reduce the level of ambient noise found
on the HF and 50 MHz bands. The (DNR) system
is especially effective during SSB operation. Any
of 15 different noise-reduction algorithms can be
selected; each of these algorithms was created to
deal with a different noise profile. You will want to
experiment with the DNR system to find the best
setting corresponding to the noise currently being
experienced.
The DNR function can be operated individually for
MAIN band and SUB band.
1. Press the [DNR] key.
2. Press and hold the [DNR] key, then rotate the
[MULTI] knob to choose one of 15 algorithms
that best reduces the noise level.
To disable the DNR system, press the [DNR] key
once more.
DNF (Digital NOTCH Filter)
The Digital NOTCH Filter (DNF) is an effective
beat-canceling filter that can null out a number of
interfering beat notes inside the receiver passband.
Because this is an Auto-Notch feature, there is no
adjustment knob associated with this filter.
The DNF function can be operated individually for
MAIN band and SUB band.
Press the [DNF] key, activate the DNF function.
To disable the DNF system, press the [DNF] key
once more.
If a very strong interfering carrier is encoun-
tered, we recommend using the IF NOTCH
filter first, as it is the most effective notching
tool in the receiver section.
NOTCH (IF NOTCH Filter)
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 pass-
band.
The NOTCH function can be operated individually
for MAIN band and SUB band.
1. Press the [NOTCH] key.
2. Rotate the [NOTCH] knob to adjust the “null” po-
sition of the Notch filter.
● The display will show the center frequency of
the Notch for 1/2 second whenever the [NOTCH]
knob is turned.
● Press and hold the [NOTCH] knob to return the
center frequency to its initial value and disable
the NOTCH filter function.
● On the filter function display area, you can check
the position of the attenuation.
To cancel the NOTCH filter, press the [NOTCH] key
momentarily.
The bandwidth of the NOTCH filter (either
narrow or wide) may be adjusted using
Menu item “IF NOTCH WIDTH” page 99.
The factory default setting is “WIDE”.
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 incoming
interference.
IF BANDWIDTH
IF BANDWIDTH
NOTCH knob
NOTCH knob
B
A
Notch
Desired Signal
QRM (Heterodyne)
