Yaesu FT-2000D, Руководство по эксплуатации

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Page 56 FT-2000D O
PERATING
M
ANUAL
IF SHIFT O
PERATION
(
SSB/CW/RTTY/PKT/AM M
ODES
)
IF Shift allows you to vary the DSP filter passband higher or lower, without changing the pitch of the incoming signal, so as
to reduce or eliminate interference. Because the carrier tuning frequency is not varied, there is no need to re-tune the
operating frequency when eliminating the interference. The total passband tuning range for the IF Shift system is ±1 kHz.
I
NTERFERENCE
R
EJECTION
(
S
IGNALS WITHIN
3
KHZ
)
Rotate the [ SHIFT
] knob to the left or right to reduce the
interference.
A
DVICE
:::::
ˆ The [ SHIFT
] knob affects the Main band (VFO-A)
only. However, you may shift the Sub band (VFO-B)
filter passband via Menu items “
044 S-iF LSB SFT ”
through “ 051 S-iF PKT-USB .”
ˆ The Sub band (VFO-B) frequency display will show
the shift value of the IF SHIFT for 3 seconds when-
ever the [
SHIFT
] knob is turned.
You may disable this feature (displaying the shift value
of the IF SHIFT) via Menu item “
015 diSP LVL IND .”
See page 117 for details.
ˆ The position of the passband set by the IF Shift can be
observed on the display.
[SHIFT] knob
SHIFT Indicator
IF
BANDWIDTH
IF
BANDWIDTH
IF
BANDWIDTH
Desired Signal Desired Signal Desired Signal
QRM QRM
Referring to Figure “
A
,” note the depiction of the
IF DSP filter as the thick line, with the [ SHIFT
]
knob in the 12 o’clock position. In Figure “ B ,” an
interfering signal has appeared inside the original
passband. In Figure “
C ,” you can see the effect of
rotating the [ SHIFT
] knob so as to reduce the in-
terference level by moving the filter passband so
that the interference is outside of the passband.
A B C