HP 83487A User Manual page 45

Table 3-3. Miscellaneous User Calibration Summary
Calibration What is calibrated
Probe calibration Probe Attenuation
Channel Skew Calibrates out the
small differences in
delay between
channels. Useful for
looking at timing
differences between
channels
External Scale Compensates for gain
or loss associated with
external devices
(calibrates vertical
scale to external
device
Measurements
Affected
Channels affected:
electrical. Any
electrical
measurement taken
with the probe
Channels affected:
optical & electrical.
Multiple channel
measurements.
Channels affected:
optical & electrical.
Any measurement
taken through an
external device
(component or
transducer
O/E User-Wavelength Calibration
This optional optical/electrical (O/E) calibration is for optical measurements
only. It compensates for the photodetector's responsivity. The vertical accu-
racy of all optical channel user wavelength measurements is dependent on
proper O/E user wavelength calibration. O/E user-wavelength calibrations
should be performed annually or whenever a new wavelength is being mea-
sured. To perform a O/E user-wavelength calibration, a CW optical source with
a known optical output power level is required. Refer to the specifications for
the plug-in module for the acceptable power level ranges.
User Calibrations—Optical and Electrical
Recommended
Key Path
Interval
Whenever a probe is Electrical Channel Setup
connected Calibrate
Calibrate probe
Before multiple Channel Setup
channel Calibrate
measurements when Skew
measuring timing
differences between
channels.
Whenever using Channel Setup
external devices External Scale
(component or
transducer)
Calibration Overview
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