Dealing With Interference; Shift Control; High Cut /Low Cut Controls (Dsp) - Yaesu FT-920 Operating Manual

enjoy the many interesting aspects of shortwave lis-
tening. Among the transmission often encountered
are:
(see table below)
(transoceanic airliners, etc.)
(satellite images, charts, and forecasts)
Popular Shotwa ve Broa dc ast B ands
Me ter Frequency Range
Band (MH z)
LW 0.150~0.285
MW 0.520~1.625
120 2.30~2.50
90 3.20~3.40
75 3.90~4.00
60 4.75~5.20
49 5.85~6.20
41 7.10~7.50
FT-920 Operating Manual
Me ter Frequency Range
Band (MH z)
31 9.35~9.90
25 11.55~12.05
22 13.60~13.90
19 15.10~15.70
16 17.55~17.90
- 18.90~19.30
13 21.45~21.85
11 25.67~26.10

Dealing with Interference

S Control
HIFT
The front panel's S control tunes the position of
HIFT
the IF passband relative to the frequency of the in-
coming signal in all modes except FM. This allows
the operator to sweep (in effect) the current IF filter
back and forth across the desired signal, eliminating
interference in the process, without changing the pitch
of the incoming signal.
The control is detented in the center (12 o'clock) po-
sition, which represents the "normal" passband cen-
ter frequency. The S control is dedicated to the
HIFT
receive mode, and does not affect your transmitted
signal characteristics (such adjustment of the trans-
mitted signal is, however, provided via Menu Items
U-59, U-60, U-62, and U-63).
Rotate the S control to the left or right to eliminate
HIFT
the interference. Careful adjustment of the S
trol may also be useful in improving the recovered
audio on excessively bassy SSB signals. Return the
S control to the center detented position to return
HIFT
to the normal default passband setting.
H C /L C Controls (DSP)
IGH UT OW UT
The DSP system's chief interference-fighting circuitry
is the passband tuning feature, which features the
H C and L C controls. These controls may
IGH UT OW UT
be used to optimize the audio bandwidth so as to
reduce interference and noise, and maximize signal-
to-noise ratio.
To activate the DSP passband filter, press the [DSP]
key (located just below the S
key contains an LED, which will glow green when the
DSP is on. Now rotate the H
roll off interference and/or noise, or to enhance the
sound of the incoming signal. A graphical represen-
tation of the relative width of the DSP passband can
be displayed on the Enhanced Tuning Scale by mak-
ing the appropriate configuration of Menu Item U-10.
See page 74 for details.
Press the [DSP] switch again to turn the DSP pass-
band filter off.
Note: Since the DSP passband filter operates in the
audio section, after the AGC detector, very strong
signals inside the IF passband but outside the DSP
con-
HIFT
control). The [DSP]
HIFT
C and L C to
IGH UT OW UT
43