Kenwood TS-930S Instruction Manual page 21

bandwidth), the passband-width varies from 500 Hz
to approximately 150 Hz.
Since an optional filters center frequency is 700 Hz
higher than that of the built-in 2.7 kHz filter, the CW
receive tone will be about 800 Hz without using the
pitch control. Fig. 5-3 shows the CW VBT function
with an optional filter.
7 NOTCH CONTROL
If a single tone such as a CW signal is superimposed on the
receive signal, turn the NOTCH ON and adjust the NOTCH
control to eliminate or minimize the beat signal. A beat of
approximately 1.5 kHz can be eliminated at the center
position of the control. In USB, CW, or AM mode, a beat
signal lower than 1.5 kHz can be eliminated by turning the
control clockwise. In LSB or FSK mode, adjust the control
counterclockwise. ;
Desired signal
Desired signal
~=—— Unwanted signal
Unwanted signal
nulled by NOTCH
> Oo
Ls |)
-2 -\ 10 +1 &4+2 KHZ ee |
BFO BFO
Notch off Notch on
Fig. 5-4 NOTCH operation (LSB mode)
8 AF TUNE circuit
During CW operation, this audio filter having a peak center
frequency of approximately 800 Hz, adjustable +400 Hz,
provides additional rejection of noise and interfering signals
whose pitch (tone) falls outside the audio passband.
Turn the AF TUNE switch ON and adjust the AF TUNE con-
trol (33) to peak the desired signal.
9 NB (noise blanker) switch
© NB1 switch:
For pulse type noise, such as generated by automotive
ignition systems, turn the NB1 switch ON. Adjusting the
NB LEVEL control varies the. blanker's threshold,
eliminating even low level noises.
NOTE: ————
If high level signal or noise is present on an adjacent frequency, do
not use excessive NB threshold LEVEL as it may distort the receiv-
ed signal. lf you are operating near other strong signals, use the RF
ATT along with the noise blanker fevel control.
e NB2 switch:
Turn on this switch if ''"woodpecker'' radar pulse noise
is the source of interference.
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