User`s manual

Depth Control: Used to specify the dB attenuation to be applied for all notches currently

implemented. However, unlike the Notch Freq and Width controls, the Depth

control is fully interactive and has instantaneous effect at all times; clicking the

Build button is not necessary for the Depth control to have effect. Range of

adjustment is 0 to -90.3dB.

Clear All Button: Clears all Notch Freq and Notch Width settings for all 16 notches and restores

the Multiple Notch filter coefficients to an allpass filter (no notches).

Filter Active Button: Used to switch the filter in and out of the process without affecting the

operation of the other filters. Button LED is illuminated RED when the filter is

in the process, and is not illuminated (GRAY) when the filter is out of the

process.

NOTE: The Filter Active button is equivalent to, and linked with, the Active

button in the associated Filter block on the Master Control Panel.

Set for DTMF Button: This button will set the first eight notches to each of the eight specific DTMF

tones. This is useful for cancelling noise introduced into phone conversation by

the DTMF tones. After the button is clicked the filter must be rebuilt.

OK Button: Use either this button or the “X” button at the upper right corner of the

window to exit the dialog and return to the Master Control panel.

A graphical description of the Multiple Notch filter and its controls follows in Figure 4-32:

Figure 4-32 Multiple Notch Filter Graphical Description