for high-frequency measurements, no anti-aliasing filter is provided in the multimeter. If you are con-
cerned about aliasing, you should add an external anti-aliasing filter.
Level Triggering
When digitizing, it is important to begin sampling at some defined point on the input signal such as when
the signal crosses zero volts or when it reaches the midpoint of its positive or negative peak amplitude.
Level triggering allows you to specify when (with respect to voltage and slope) to begin sampling. Refer to
for more information.
About Digitize Mode
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Digitizing is available only for the 34465A/70A and requires the DIG option.
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Digitizing allows you to take samples of the input signal, at a specified Sample Rate (for example, 50 kHz)
or Sample Interval (for example, 20 µS). You can specify the Duration as either an amount of Time or a num-
ber of Readings (samples). You can use either auto, external, or level triggering. After pressing
[Acquire]
,
press
Acquire > Digitize
. You can then select the digitizing/triggering parameters. After configuring the
digitizing parameters, press
[Run/Stop]
. Digitizing will begin when the specified trigger event occurs.
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Digitize mode is available only from the front panel and can only be used for DCV or DCI measurement
functions.
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When you specify digitizing settings that conflict with present settings, the instrument displays a message,
and in most cases, adjusts settings to legal values. For example, if you configure digitizing for a greater
sample rate than can be achieved with the present integration time (NPLC setting), the instrument displays
a message and reduces the integration time. When you see a displayed message, such as
NPLC setting
reduced to achieve digitize rate/interval
, you can press
Shift > Help > 1 View the last message dis-
played > Select
to view more information.
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The DIG option increases the maximum reading rates from 5k readings/s (standard) to 50k readings/s (max-
imum).
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The DIG option enables pretriggering, level triggering, and trigger delay capability.
Measurement Tutorial
178
Keysight True
volt
Series Operating and Service Guide
