Icom IC-7000 instruction manual Twin PBT operation, PBT Operation Example

5FUNCTIONS FOR RECEIVE

■Twin PBT operation

General PBT (Passband Tuning) function electronically narrows the IF passband width by shifting the IF fre- quency to slightly outside of the IF filter passband to reject interference. This transceiver uses the DSP cir- cuit for the PBT function. Moving both [PBT/M-ch/RIT]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. 127)

➥When M-1is selected, push [F-3FIL] 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]controls to the center posi- tions, push [PBT/M-ch/RIT(CLR)]for 1 sec.

The limit of the variable range depends on the pass- band width and mode. The edge of the variable range is half of the passband width, and PBT is adjustable in 100 (AM) or 25 Hz steps (other modes).

[PBT/M-ch/RIT(CLR)] switch/[PBT] (inner) control [PBT/M-ch/RIT] indicator

[F-3]

[PBT] (outer) control [MENU/GRP]

Dot indicator appears

when PBT is activate Selected IF filter

Passband width

Shift frequency

Popup indicator appears

• [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.

PBT OPERATION EXAMPLE

Both controls at	Cutting a lower	Cutting both higher and
center position	passband	lower passbands

Passband

Passband

IF center frequency	Interference Desired signal	Interference		Interference
			Desired signal

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