Using The Twin Pbt - Icom IC-7610 Basic Manual

Using the Twin PBT

SSB, CW, RTTY, PSK and AM modes
To reject interference, the Twin PBT (Passband
Tuning) narrows the IF passband width by
electronically shifting the IF frequency slightly above
or below the IF center frequency. The IC-7610 uses
DSP for the PBT function.
1. Rotate inner (PBT1) and outer (PBT2)
TWIN PBT
CLR
in the opposite direction from each other.
Inforration
L
• Match both the
TWIN PBT
outer(PBT2)filtersbeforeoperatingtheTwinPBT.
• Rejects interference of both higher and lower
passbands.
• If you rotate the control too much, the received
audio may not be heard because the passband
width is too narrow.
• Displays the passband width and shift value.
• Hold down
TWIN PBT
PBT setting.
• The PBT is adjustable in 50 Hz steps in the SSB,
CW, and RTTY modes, and 200 Hz in the AM
mode. In this case, the center shift value changes
in 25 Hz steps in the SSB, CW, and RTTY modes,
and 100 Hz in the AM mode.
• Rotating both the inner and outer controls together
to the same position shifts the IF left or right.
2. Hold down for 1 second to display the
FILTER
current passband width and shift frequency.
• Opens the FILTER screen.
3. To close the FILTER screen, push
NOTE: While rotating
TWIN PBT
This comes from the DSP unit and does not indicate an
equipment malfunction.
PBT is OFF
PBT2
IF center frequency
(inner) (PBT1) and
CLR
for 1 second to clear the
CLR
.
EXIT
, you may hear noise.
CLR
Cutting the
lower passband
PBT2
PBT1
Desired
Interference
signal
RECEIVING AND TRANSMITTING
• When rotating
TWIN PBT
Filter width Shifting value
• The FILTER screen when rotating
SFT: Shift value
IF center frequency
PBT1
PBT2
Cutting both higher and
lower passbands
PBT1
Passband
Interference
4-3
TWIN PBT
CLR
FILTER
CLR
Passband width
(Duplicated with PB1 and PB2)
Selected
IFfilter
TWIN PBT
Passband center frequency
BW:
Passband width
PBT2
PBT1
Passband
Desired Interference
signal
4
1
2
3
4
5
6
7
8
9
10
11
CLR
12
13
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15
16
17
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