Yaesu FTDX9000D Operation Manual

Also see for FTDX-9000D: Operation manual Brochure & specs Update guide Update guide Update guide

Contents

Page 25FTDX9000D OPERATION MANUALNTCH SwitchThis button turns the main band (VFO-A) IF notchfilter on and off. When the IF notch filter is activated,the LED inside the button will glow red. The NotchFilter center frequency is adjusted via the NTCH knob,described in the previous section.Advice The width of the notch may be set to either “Wide”or “Narrow” via Menu #82 (IF-NOTCH-WIDTH)in the RX DSP Menu Group. Setting this selec-tion to “Narrow” will provide a very sharp notch,with minimal disturbance to the incoming signalwave-form. The tuning rate of the Notch Filter being ratherslow, it frequently is useful to use the Audio Scopeof the TFT (either the Audio Spectrum Scope orthe Waterfall display) to adjust the center fre-quency of the IF Notch Filter. In the Waterfalldisplay mode, the notched area will appear morewhite than the background screen, while on theAudio Spectrum Scope screen the notched areawill appear as a “hole” in the noise.DNF SwitchThis button turns the main band (VFO-A) DigitalNotch Filter on and off. When the Digital Notch Fil-ter is activated, the LED indicator will glow red. Thisis an automatic circuit, and there is no adjustment knobfor the DNF.R.FLT SwitchThis button selects the bandwidth for the main band(VFO-A) receiver's first IF Roofing Filter. Availableselections are 3 kHz, 6 kHz, 15 kHz, or Auto, and theLED indicator will change according to the bandwidthselected.AdviceBecause the roofing filter is in the first IF, the protec-tion it provides against interference is quite signifi-cant. When set to AUTO, the SSB bandwidth is 6 kHz,while CW is 3 kHz and FM/RTTY are 15 kHz. On acrowded SSB band, however, you may wish to selectthe 3 kHz filter, for the maximum possible interfer-ence rejection.DNR SwitchThis button turns theMain band (VFO-A) Digital NoiseReduction circuit on and off. When the Digital NoiseReduction is activated, the LED inside the button willglow umber. Adjustment of the Noise Reduction levelis provided by the DNR knob, described in the nextsection.CONT DNR KnobCONT KnobThe inner CONT knob selects the desired sub band(VFO-B) CONTOUR filter response. The CONTOURfilter is engaged via the CONT switch, described inthe next section.DNR KnobThe outer DNR knob selects the optimum Main Band(VFO-A) Digital Noise Reduction response. The NoiseReduction circuit is engaged via the DNR switch, de-scribed in section above.CONT ButtonThis button turns the sub band (VFO-B) CONTOURfilter on and off. When the CONTOUR filter is acti-vated, the LED inside the button will glow umber. Ad-justment of the CONTOUR filter’s center frequencyis provided by the CONT knob, described in sectionabove.Quick NoteThere are times, when you’re trying to remove inter-ference with a sharp DSP filter, that the remaining sig-nal has a somewhat unnatural sound. this is caused bythe cutting of some frequency components, leavingother components in excess. The CONTOUR filterallows you (especially) to roll off certain frequencycomponents inside the remaining passband, but in asmooth manner that helps restore a natural sound and/or raise intelligibility.Advice The action of the CONTOUR filter (either null-ing or peaking of frequency components as youadjust the center frequency) may be adjusted viaMenu item “RX DSP 79 MAIN-CONTOUR-WIDTH.” The adjustment range includes settingsof -15 dB (nulling) to +10 dB (peaking). The Audio Spectrum Scope (including the Wa-terfall displays) on the Oscilloscope page of theTFT can be particularly useful when adjusting theCONT control (see section 29 above), as you canobserve the position of the null or peak in the au-dio passband.FRONT P ANEL C ONTROLS