Figure 3 81: The Sampling Head Fnc's Pop Up Menu - Tektronix 11801C User Manual

Sampling Heads

Figure 3 81: The Sampling Head Fnc's Pop up Menu

External Channel Attenuation enables you to enter a number representing
the external attenuation of a channel. Once the number has been entered
(1 is the default), the instrument then uses the total attenuation factor in
scaling measurement results. Note that the attenuation factor is also applied
to Vertical Size.
Total attenuation is the product of the external attenuation times the hard
ware attenuation of the probe or sampling head. The hardware attenuation
factor is displayed in the Identify pop up menu of the Utility1 major menu.
External attenuation can be specified either as a scaling factor (2, 5, 10 etc.)
or in decibels (dB). Decibels (dB) is related to the attenuation factor by the
formula:
dB + 20 log (attenuation factor)
10
The range for dB is -120 to +120.
Negative dB values or fractional attenuation factors indicate gain, rather than
attenuation.
External channel attenuation is a feature of the mainframe, not of the sam
pling head. Thus, this feature applies to all sampling heads.
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