INTERFERENCE REJECTION(SIGNALS WITHIN 3KHZ)

IF SHIFT OPERATION (SSB/CW/RTTY/PKT/AM MODES)

IF Shift allows you to vary the DSP filter passband higher or lower, without changing the pitch of the incoming signal, so as to reduce or eliminate interference. Because the carrier tuning frequency is not varied, there is no need to re-tune the operating frequency when eliminating the interference. The total passband tuning range for the IF Shift system is ±1 kHz.

Rotate the [SHIFT] knob to the left or right to reduce the interference.

SHIFT Indicator

[SHIFT] knob

ADVICE:

￿The [SHIFT] knob affects the Main band (VFO-A) only. However, you may shift the Sub band (VFO-B) filter passband via Menu items “042 S-iF LSB SET” through “049 S-iFPKT-USB.”

￿The position of the passband set by the IF Shift can be observed on the display.

Referring to Figure “A,” note the depiction of the IF DSP filter as the thick line, with the [SHIFT] knob in the 12 o’clock position. In Figure “B,” an interfering signal has appeared inside the original passband. In Figure “C,” you can see the effect of rotating the [SHIFT] knob so as to reduce the in- terference level by moving the filter passband so that the interference is outside of the passband.

A B C

Desired Signal

Desired Signal

Desired Signal

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

QRMQRM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IF

 

 

 

 

IF

 

 

 

 

 

IF

 

BANDWIDTH

BANDWIDTH

BANDWIDTH

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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FT-2000 OPERATING MANUAL