HP 53131A, Operating Manual

Page: 107 / 196

Chapter 2 Operating Your Universal Counter
Using the MATH Menu Keys
Operating Guide 2-31
2
Example Procedure for Setting the Offset From
the Last Measurement Value
The SET OFFSET ? menu item uses the negative of the last measurement
value, rounded to eleven digits, to set the OFFSET. Thus, any difference
in the offset (or now the reference value) and the current measurement
value is displayed.
Let’s assume you are measuring the frequency of a stable source, but you
are only interested in the least significant digits of the measurement.
Use the
SET OFFSET ? menu item to configure the appropriate OFFSET
value.
Your task is to measure a stable source to obtain the changes in theleast
significant digits.
1 Cycle POWER key to preset the Counter.
2 Change gate time to 15.0 seconds on GATE menu.
3 To demonstrate SET OFFSET?, connect a 10 MHz sine wave signal to
channel 1 of the Counter, and set up the Counter to measure the
frequency of the signal. (Refer to the section in this chapter titled
“To Measure Frequency” if needed.)
10.0000000001 MHz is displayed.
4 Press Scale & Offset key until SET OFFSET ? is displayed.
5 Press Enter key.
OFFS:
−
10.00000 MHz is displayed, for example.
Note that this value represents the last measurement of the input signal
rounded to eleven digits. The Counter uses it as the reference offset value,
and reverses the sign from + to
−
.