12 REJECTING INTERFERENCE

NOISE BLANKER

Noise Blanker was designed to reduce pulse noise such as that generated by automobile ignitions. Noise Blanker does not function in FM mode.

Press [7/ NB/ LEVEL] to toggle between the Noise Blanker ON and OFF.

•“NB” appears when the function is ON.

You can further adjust the Noise blanker level from 1 to 10. The default level is 6.

Press [FUNC], [7/ NB/ LEVEL], then turn the MULTI/ CH control to adjust the noise blanker level.

•“NB LEVEL” and the current level appear on the sub dot-matrix display.

Note: Noise Blanker is available only for the main transceiver in SSB, CW, FSK, and AM modes.

PRE-AMPLIFIER

Switching the Pre-amplifier OFF may help reduce interference from adjacent frequencies.

Press [PRE/ LOCK A] to toggle between the Pre-amplifier ON and OFF.

•“PRE” appears when the function is ON.

The ON/OFF setting will be automatically stored in the current band. Each time you select the same band, the same setting will be automatically selected.

The frequency range of each band is provided in the following table (under “ATTENUATOR”).

Note: If the same frequency (144 MHz or 430 (440) MHz) band is selected on both the main transceiver and the sub-receiver, the pre-amplifier can be switched ON or OFF for both receivers. This is because the main transceiver and sub-receiver share the same antenna.

ATTENUATOR

The Attenuator reduces the level of received signals. This function is useful when there is strong interference from adjacent frequencies.

Press [ATT/ F LOCK] to toggle the Attenuator ON and OFF.

•“ATT” appears when the function is ON.

The ON/OFF setting will be automatically stored in the current band. Each time you select the same frequency band, the attenuator setting will be automatically recalled.

The frequency range of each band is shown below.

Frequency Bands

Pre-amplifier

Attenuator

(MHz)

(Default)

(Default)

0.03 ~ 2.5

OFF

OFF

 

 

 

 

2.5

~ 4.1

OFF

OFF

 

 

 

 

4.1

~ 7.5

OFF

OFF

 

 

 

7.5 ~ 10.5

ON

OFF

 

 

 

 

10.5

~ 14.5

ON

OFF

 

 

 

 

14.5

~ 18.5

ON

OFF

 

 

 

 

18.5

~ 21.5

ON

OFF

 

 

 

 

21.5

~ 25.5

ON

OFF

 

 

 

 

25.5

~ 30.0

ON

OFF

 

 

 

 

30.0

~ 60.0

ON

OFF

 

 

 

 

118

~ 300

ON

OFF

 

 

 

 

300

~ 512

ON

OFF

 

 

 

 

1240

~ 1300

Always ON

Always OFF

 

 

 

 

Note:

◆If the same frequency (144 MHz or 430/ 440 MHz) band is selected on both the main transceiver and the sub-receiver, the attenuator can be switched ON or OFF for both receivers. This is because the main transceiver and sub-receiver share the same antenna.

◆Available receiving frequencies in the above frequency bands vary, depending on the market code. Refer to the Specifications {page 106} for details.

◆If 118 ~ 135.995 MHz, 155 ~ 173.995 MHz or 220 ~ 229.995 MHz is selected for the sub-receiver, the pre-amplifier cannot be turned ON (K-type only).

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