HP 54750A, User Manual, Page: 83 / 478

Probe Calibration
Probe calibration allows the instrument to establish the gain and oset of
specic probes that are connected to a channel of the instrument, and then
apply those factors to the calibration of that channel.
1. T o perform a probe calibration, press:
4
Channel
5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Calibrate
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Calibrate Probe
F or active probes the instrument can identify through the probe power
connector , like the HP 54701A, the instrument automatically adjusts the
vertical scale factors for that channel, even if a probe calibration is not
performed.
F or passive probes or non-identied probes , the instrument adjusts the
vertical scale factors only if a probe calibration is performed.
2. If you do not perform a probe calibration but want to use a passive probe ,
enter the attenuation factor by pressing:
4 Channel 5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
external scale
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Attenuation
Y ou can use the probe calibration to calibrate any network, including probes
or cable assemblies . The instrument calibrates the voltage at the tip of the
probe or the cable input.
If the probe being calibrated has an attenuation factor that allows the
instrument to adjust the gain (in hardware) to produce even steps in the
vertical scale factors , the instrument will do so . Typically , probes have
standard attenuation factors , such as divide by 10, divide by 20, or divide
by 100. If the probe being calibrated has an unusual attenuation, like 3.75,
the instrument may have to adjust the vertical scale factors to an unusual
number , such as 3.75 V/div .
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