Agilent Technologies 53181A, Operating Manual

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Chapter 1 Getting Started
The Display Annunciators at a Glance
1-8 Operating Guide
1
The Display Annunciators at a Glance
Annunciator Indication
Period
Counter is set to measure Period.
Freq Counter is set to measure Frequency.
Ch 1 Counter’s channel 1 is selected to measure an input signal.
Ch 2
Counter’s channel 2 is selected to measure an input signal.
Limit Counter is limit testing and the current measurement exceeds the user-
entered limits.
ExtRef
Counter is set to use the signal connected at rear panel Ref In
connector as the timebase (TIMEBAS: EXT); or Counter is set to
automatically (TIMEBAS: AUTO) select the timebase and has chosen
the signal connected at the rear panel Ref In connector.
Hz The displayed data is in units of Hertz.
M The prefix for the units of the displayed data is mega (10
6
).
µ
The prefix for the units of the displayed data is micro (10
−
6
).
s The displayed data is in units of seconds.
Gate The gate is open. Before a measurement cycle starts, this annunciator
is OFF, indicating the gate is closed. During a measurement cycle, the
annunciator is ON, indicating the gate is open.
Period Freq Ch 1 Ch 2 Limit ExtRef
MHz
µs
Gate