HP 83481A, User Manual, Page: 61 / 98

Calibration Overview
User Calibrations|Optical and Electrical
T able 3-3. Miscellaneous User Calibration Summary
Calibration What is calibrated Measurements Aected Recommended Interval K ey Path
Probe
calibration
Probe Attenuation Channels aected: electrical.
An y electrical measurement
taken with the probe
Whenever a probe is
connected
4
Electrical Channel Setup
5
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Calibrate
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Calibrate probe
Channel Skew Calibrates out the small
dierences in dela y
between channels. Useful
for looking at timing
dierences between
channels
Channels aected: optical &
electrical. Multiple channel
measurements, such as
Dierential TDR
Before multiple channel
measurements when
measuring timing dierences
between channels.
4
Channel Setup
5
FFFFFFFFFFFFFFFFFFFFFFFFFF
Calibrate
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Skew
External Scale Compensates for gain or
loss associated with
external devices
(calibrates vertical scale
to external device)
Channels aected: optical &
electrical. An y measurement
taken through an external
device (component or
transducer)
Whenever using external
devices (component or
transducer)
4
Channel Setup
5
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External Scale
O/E User-W avelength Calibration
This optional optical/electrical (O/E) calibration is for optical measurements
only . It compensates for the photodetector's responsivity . The vertical
accuracy 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
measured. T o perform a O/E user-wavelength calibration, a CW optical
source with a known optical output power level is required. Refer to the
specications for the plug-in module for the acceptable power level ranges .
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