Twin Pbt Operation - Icom IC-7000 Instruction Manual

5
FUNCTIONS FOR RECEIVE

■ 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 passband
to reject interference. This transceiver uses the DSP
circuit for the PBT function. Moving both [PBT
controls to the same position shifts the IF.
➥ Push [PBT/M-ch/RIT] momentarily to select the
twin PBT function, if the M-ch-RIT is selected.
• [PBT/M-ch/RIT] indicator (Green) lights.
• The passband settings window shows the passband
width and shift frequency graphically. (The passband
settings window can be turned OFF in the display set
mode. p. 125)
➥ When M M - - 1 1 is selected, push and hold [F-3 F F I I L L ] for
1 sec. to enter the filter set mode. Current passband
width and shift frequency is displayed in the filter set
mode.
➥ To set the [PBT
/M-ch/RIT
tions, push and hold [PBT
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
100 (AM) or 25 Hz steps (other modes).
PBT OPERATION EXAMPLE
Both controls at
center position
IF center frequency
77
/M-ch/RIT
] controls to the center posi-
)] for 1 sec.
(
/M-ch/RIT
CLR
Cutting the lower
passband
Interference Desired signal
[PBT (CLR)] switch/[PBT] (inner) control
/M-ch/RIT
[PBT/M-ch/RIT] indicator
]
[PBT] (outer) control
Dot indicator appears
when PBT is activate
Passband
width
Shift
frequency
• [PBT] controls should normally be set to the center posi-
tions (PBT setting is cleared) when there is no interfer-
ence.
• When PBT is used, the audio tone may be changed.
• Not available for FM or WFM modes.
• While rotating [PBT], noise may occur. This comes from
the DSP unit and does not indicate an equipment mal-
function.
Passband
Interference
[F-3]
[MENU/GRP]
Selected IF filter
Popup indicator appears
Cutting both higher and
lower passbands
Passband
Interference
Desired signal