Twin Pbt Operation - Icom IC-7200 Instruction Manual

■ Twin PBT operation

The general PBT (Passband Tuning) function elec-
tronically narrows the IF passband width by shifting
the IF frequency slightly outside of the IF filter pass-
band to reject interference. This transceiver uses the
DSP circuit for the PBT function.
By rotating both [TWIN PBT] controls (inner/outer;
PBT1 and PBT2) with the same position, PBT func-
tions as an IF shift control.
The limit of the variable range depends on the pass-
band width and mode. The limit of the variable range
is half of the passband width, and PBT is adjustable
in 200 Hz (AM) or 50 Hz (other models) steps.
PBT OPERATION EXAMPLE
Both controls at
center position
TWIN PBT
IF center frequency
• The [TWIN PBT] controls should normally be set
to the center positions (PBT setting is cleared)
when there is no interference.
• When PBT is used, the audio tone may be
changed.
• While rotating the [TWIN PBT] controls, noise
may occur. This comes from the DSP unit and
does not indicate an equipment malfunction.
Cutting the lower
passband
TWIN PBT
Passband
Interference Desired signal
FUNCTIONS FOR RECEIVE
MODE TS
TUNER FILTER
SPCH
[TWIN PBT]
Cutting both higher and
lower passbands
TWIN PBT
Interference
Desired signal
5
NB NR ANF
METER
V/M 1 A/B 2 3
SPLIT
=
1.8 3.5 7
4 5 6
MW M-CL AGC
10 14 18
7 8 9
COMP SCAN VOX
21 24 28
.
0
F-INP ENT
RIT MNF
GENE 50
BAND
P.AMP
ATT
M-CH/RIT
SET
1
2
3
4
5
6
7
8
9
10
Passband
11
12
13
Interference
14
15
16
17
18
19
20
21
46