04 DSP28There are two settings on the manual notch filter: Normal and Wide. You can select one of two bandwidths for the notchfilter (Figure 4-9). For a simple beat frequency, Normal is effective. If there is an interfering SSB signal, or in the event thetarget signal is also trimmed by LO CUT/ HI CUT, a Wide setting of the Notch filter used in combination with LO CUT/HICUT may be effective.Figure 4-9 Results of Amplitude and Frequency Analysis of the Manual Notch FilterThe auto notch filter inherited from the TS-2000/X and the TS-870S also has been improved to deliver better capability totrack the beat frequency. The enhanced notch filter has good effect even on a relatively weak beat signal. The auto notchfilter is sharper, like a needle, than the manual notch filter and can minimize the impact of the notch on the audio.Hints and Tips● What is a auto notch filter?The "auto notch filter" from KENWOOD processes the signal at the IF stage. In other words, it is the IF auto notch filter. And thenotch filters that process the signal at the AF stage are known as "Beat Cancel (BC1, BC2)".Whether the notch is an IF process or AF process can be determined by the actual operation. In the case of an IF notch, the Smeter deflection decreases together with beat suppression upon receiving signals when the S meter deflects and when the notchfunction is turned on. In contrast, in the case of an AF notch, the S meter deflection remains unchanged even though there is beatsuppression. Note that whether the operation is one at the IF stage or the AF stage may vary depending on the product , evenwhen two products are of the same name.4.3.4 Noise Blanker (NB2)Refer to 4.6.2 Noise Blanker NB2 (IF Processing).