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5-19
5
FUNCTIONS FOR RECEIVE
■
Notch function
This transceiver has auto and manual notch functions.
The auto notch function uses DSP to automatically
attenuate beat tones, tuning signals, etc., even if they
are moving. The manual notch can be set to attenuate
a frequency via the [NOTCH] control.The auto notch
can be used in SSB, AM and FM mode. The manual
notch can be used in SSB, CW, RTTY, PSK and AM
modes.
➥
Push
NOTCH
to toggle the notch function be-
tween auto, manual and OFF in the SSB and AM
modes.
➥
Push
NOTCH
to turn the manual notch function
ON or OFF in the CW, RTTY, PSK modes.
➥
Push
NOTCH
to turn the auto notch function ON
or OFF in the FM mode.
• [NOTCH] indicator above this switch lights green.
• Hold down
NOTCH
for 1 second to select the notch
filter width for manual notch from wide, middle and nar-
row.
• Set to attenuate a frequency for manual notch via the
[NOTCH] control.
• “
AN
” appears when auto notch is in use.
• “
MN
” appears when manual notch is in use.
While tuning the manual notch, noise may be
heard. This comes from the DSP unit and does not
indicate an equipment malfunction.
■
Digital selector
The digital selector manually adjusts the center fre-
quency of the automatic pre-selector. The available
frequency is between the 1.5 MHz to 29.999999 MHz
range.
The automatic pre-selector adds selectivity ahead of
the 1st mixer. This reduces intermodulation distortion
from strong signals near the received frequency.
The automatic pre-selector tracks the frequency tun-
ing, changing its center frequency in discrete steps.
q
Push
DIGI-SEL
to turn the digital selector ON or
OFF.
• [DIGI-SEL] indicator above this switch lights green.
w
Rotate [DIGI-SEL] control to adjust the center fre-
quency.
NOTE:
•
When rotating the main dial while the digital selec-
tor is activated, mechanical noise may be heard
due to the switching noise from internal relays.
• The preamp (P.AMP1 or P.AMP2) cannot be used
while the digital selector is activated.
[NOTCH] control
NOTCH
[DIGI-SEL] control
DIGI-SEL
• Manual notch indication
• Auto notch indication