Yaesu FTDX9000D Operation Manual

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

Contents

Page 70 FTDX9000D OPERATION MANUALMAIN (VFO-A) SUB (VFO-B)MAIN(VFO-A)WIDTH (BW) cntrol may beobserved on the TFTSUB(VFO-B)WIDTH (BW) cntrol may beobserved on the TFTWIDTH (IF DSP B ANDWIDTH ) T UNING (SSB/CW/RTTY/PKT M ODES )The IF Width tuning system allows you to vary the width of the DSP IF passband, so as to eliminate interference. Moreover,the bandwidth may actually be expanded from its default setting, should you wish to enhance incoming signal fidelity wheninterference on the band is low.Main (VFO-A) Band IF Width OperationRotate the Main (VFO-A) WIDTH knob (# ) to adjustthe bandwidth. Counter-clockwise rotation reduces the band-width, while clockwise rotation increases the bandwidth.Sub (VFO-B) Band IF Width Operation1. Press the Sub (VFO-B) band’s RX switch to en-gage Dual Receive operation.2. Rotate the Sub (VFO-B) WIDTH knob (# ) toadjust the bandwidth. Counter-clockwise rotation re-duces the bandwidth, while clockwise rotation in-creases the bandwidth.Referring to Figure B, you can see the default bandwidthwith the WIDTH control set to the 12 o’clock position.By rotating the WIDTH knob to the left, the bandwidth willnarrow (see Figure (A)), while rotation of the WIDTH knob tothe right, as depicted in Figure (C), will widen the bandwidth.The default bandwidths, and total bandwidth adjustment range,will vary according to the operating mode:SSB Mode200 Hz ~ 2.95 kHz (bandwidth at 12 o'clock position ofWIDTH : 2.4 kHz).CW/RTTY/PKT Modes25 Hz ~ 2.4 kHz (bandwidth at 12 o'clock position of WIDTH :500 Hz).Interference Rejection (Signals within 3 kHz)AdviceYou may observe the effects of adjustment of theWIDTH control on the TFT.For example, in Figure (A) you can see how interference has ap-peared both on the high and low sides of the desired signal. By ro-tating the WIDTH control, as shown in Figure (B), the interfer-ence from one side can be eliminated, and by re-positioning theSHIFT control (Figure (C)), the interference on the opposite sidecan be removed, without re-introducing the interference previouslyeliminated in Figure (B).AdviceFor best interference reduction, the Width and Shift features are theprimary tools you should use. After narrowing the bandwidth (Width)and/or adjusting the center of the passband (Shift), the Contour con-trol may also yield additional signal-enhancement benefits on thenet residual bandwidth. What's more, the IF Notch Filter (see thenext section) may also be utilized, inconjunection with the threeother filter systems, to significant advantage.Using IF Shift and Width TogetherThe IF SHift and Variable IF Width featuress together form a very effective interference-fighting filtering system.IF BANDWIDTH IF BANDWIDTH IF BANDWIDTHB CAQRMQRMQRM QRM QRMQRMDesired SignalIF BANDWIDTH IF BANDWIDTH IF BANDWIDTHB CAMAIN(VFO-A)WIDTH knobSUB(VFO-B)WIDTH knobSUB(VFO-B)RX switchWIDTH system may beobserved on the