HP 83487A User Manual page 54

Calibration Overview
User Calibrations—Optical and Electrical
External Scale
Both optical and electrical channels have an External scale setting which
allows the user to enter in an offset value to compensate for gains or losses not
associated with the device under test. This feature is useful for adjusting out
the effects of devices such as test fixtures and attenuators so that the reading
on the display gives the measurement value associated with only the actual
device under test.
To adjust the external scale
1 Press the plug-in module's front-panel channel SETUP key.
2 Press External scale, and set the Atten units to "decibel".
3 Press Attenuation, and enter the appropriate values.
Figure 3-6. External Scale Menu
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