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21
5
RECEIVE AND TRANSMIT
■
Function for receive
The IF shift function electronically narrows the pass-
band frequency of the IF (intermediate frequency)
and cuts out higher or lower frequency components
of the IF to reject interference. The function shifts the
IF frequency up to ±1.2 KHz in SSB/CW/RTTY
modes and up ±250 Hz in CW-narrow/RTTY narrow
modes. The IF shift is not available in AM mode.
IF SHIFT OPERATION EXAMPLE
• Adjust the [SHIFT] control for a minimum interfer-
ence signal level.
• When IF shift is used, the audio tone may be
changed.
• Set the IF shift control to its center position when
there is no interference.
SHIFT
SHIFT
SHIFT
IF center frequency
Interference
Desired signal
Passband
Both controls at
center position
Cutting a lower
passband
Cutting higher
passbands
Interference
Desired signal
Passband
ï
IF shift function
ï
RIT function
The RIT (Receive Incremental Tuning) function com-
pensates for off-frequencies of communicating sta-
tions. The function shifts the receive frequency up to
1.2 KHz without moving the transmit frequency.
q
Rotate the RIT control to cancel the off-frequen-
cies.
• “
” appears on the display.
• The transmit frequencies are not shifted.
w
To cancel the RIT func-
tion, rotate the RIT con-
trol to the center
position.
• “
” disappears.
RIT off position
ï
Preamp
The preamp amplifies received signals in the front
end circuit to improve the S/N ratio and sensitivity.
Turn this function ON when receiving weak signals.
➥
Push [P.AMP] to toggle between preamp or turn
the preamp OFF.
• Preamp functions below 1.59999 MHz, but sensitivity
may reduce in some cases.
Appears when the
preamp ON.