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Using the Attenuator
Setting Up the Attenuation
Resetting the Attenuation Factor
To reset the attenuation factor, press and hold ATT until the valu e
resets (this takes approximately two seconds). The attenuation
factor resets so that the filter attenuation is zero, that is
Att(dB) = Cal(dB)

Entering a Calibration Factor

The calibration factor is shown at th e bottom left of the display
Figure 2-3 The Calibration Factor on the Display
This factor does not affect the filter attenuation. It is used to offset
the values for the attenuation factor.
There are two ways of entering the calibration factor.
•by editing, and
•by transferring
Editing the Calib ration Factor
You would use this, for example, to enter an offset to compensate
for the insertion loss (a ttenuation) of your hardware setup .
The filter attenuation stays con stan t whi le you edit the calib rat ion
factor. This means that the attenuation factor , shown on the display,
changes according to the formula below (from equation (1)):
AttNEW(dB) = Attfilter(dB) + CalNEW(dB) = AttOLD(dB) -CalOLD(dB) + CalNEW(dB)
To edit an external calibration factor,