Agilent Technologies 34420A, Руководство пользователя

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To Make Null (Relative) Measurements
Each null measurement, also called relative, is the difference between a
stored null value and the input signal. See page 77.
Reading = measurement – null value
•
You can make null measurements on any function or channel. You can
set a null for each channel and function independently. The meter
remembers the null value when you switch between input channels or
functions.
•
To null the test lead resistance for more accurate two-wire ohms
measurements, short the ends of the test leads together and then
press
Null
.
•
The first reading taken after you press
Null
is stored as the null value
in the Null Register. Any previously stored value is replaced with the
new value.
•
After enabling null, you can edit the stored null value by
pressing
Shift >
(Menu Recall). This takes you to the “NULL
VALUE” command in the MATH MENU ( only if null is enabled ). Go
down to the “parameter” level, and then edit the displayed value.
Enables null operation;
Press again to disable
Null
annunciator is on when
null operation is enabled
2
Chapter 2 Front-Panel Operation
To Make Null (Relative) Measurements
45