FT-950

Operating Manual

pressing the [WIDTH] button), and IF SHIFT still is operational (requires pressing the [SHIFT] button). For many applications, you may find that simple pressing the [NAR] button instead of adjustment of the [WIDTH] knob, may be satisfactory for interference reduction

When you press the [NAR] button in the FM mode, both the transmit and receive bandwidths are narrowed.

IF NOTCH Filter Operation (SSB/CW/RTTY/PKT/AM Modes)

The IF NOTCH filter is a highly-effective system that allows you to slice out an interfering beat note or other carrier signal from inside the receiver passband.

1.Press the [NOTCH] button. The LED inside the [NOTCH] button glows orange. The [SELECT] knob works as Notch knob.

2.Press the [SELECT] knob to activate the Notch filter. The current “null” position of the NOTCH filter will appear in the NOTCH indicator on the display.

3.Rotate the [SELECT] knob to adjust the “null” position of the Notch filter.

4.Press the [CLEAR] button to move the “null” position to center.

5.To cancel the NOTCH filter, press the [SELECT] button once more. The graphic disappears from the NOTCH indicator on the display, confirming that the NOTCH filter is no longer operation.

Advice:

The IF NOTCH Filter selection will be memorized independently on each VFO stack of the VFO-A and VFO-B.

The width of the IF NOTCH null may be adjusted using Menu item “072 RGEN NOTCH W.” Both “Wide” and “Narrow” selections are available, with “Narrow” providing the least disruption of the “desired” signal.

When the optional DMU-2000 Data Management Unit is connected, the effect of the IF NOTCH filter may be observed on the Audio Scope (on the “Oscilloscope” page). The Notch will be observed as a “dip” in the noise platform observed. What’s more, the “Waterfall” display may be used to observe the effect of the IF NOTCH filter, which will appear as a white area in the colored background area.

The performance of the IF NOTCH filter is shown in Figure (A), where the effect of rotation of the [SELECT(NOTCH)] knobs is depicted. In Figure (B) you can see the notching effect of the IF NOTCH filter as you rotate the [SELECT(NOTCH)] knobs to

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Vertex Standard Co., Ltd.

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Vertex Standard FT-950 manual If Notch Filter Operation SSB/CW/RTTY/PKT/AM Modes