HP 8920A, Руководство пользователя

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Chapter 3, Operating Overview
Using Measurement Limit Indicators
Using Measurement Limit Indicators
The LO LIMIT and HI LIMIT functions are used to define a measurement
“window” to alert you to measurements that are outside these limits. When limits
are assigned, Lo and/or Hi appear by the measurement.
A measurement that goes above or below the defined limits causes three things to
happen:
1. A message appears at the top of the screen indicating a limit was exceeded.
2. The Lo or Hi indicator by the measurement flashes.
3. The Beeper beeps if it is has been enabled in the CONFIGURE screen.
Limits are helpful when you can’t watch the Test Set’s display while you are
making an adjustment on the equipment you are testing or repairing. They are also
a convenient way of alerting you to long-term measurement drift without having
to observe the screen.
To Set A HI and/or LO LIMIT
1. Position the cursor in front of the unit-of-measure for the measurement that you are set-
ting limits for.
2. Press and release the SHIFT key, then the down-arrow key to access the LO LIMIT
function, and enter the measurement’s low-limit value and its unit-of-measure.
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3. Press and release the SHIFT key, then the up-arrow key to access the HI LIMIT func-
tion, and enter the measurement’s high-limit value and its unit-of-measure.
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1. The fundamental unit for the LIMITs does not have to be the same as the measure-
ment’s units. For instance; when measuring AC Level in Volts, you can set HI and LO
LIMITs in units of dBm.