HP 53132A Assembly And Service Manual page 106

Chapter 2 Service
About the HP 53131A/132A Calibration Menu
4 Press any one of the arrow keys until your calibration choice
(that is, CAL: OFFS2? , CAL: GAIN 1? , CAL: GAIN 2? , CAL: TI QUIK? ,
CAL: TI FINE? , or CAL: TIMEBAS? ) is displayed.
Note that the timebase choice (CAL: TIMEBAS?) only appears when the
Timebase Option is installed.
5 Press Enter key.
A scrolling message is displayed.
6 Follow the instructions in the scrolling message, and press Enter
key to start the calibration.
The Counter momentarily displays CALIBRATING , and then displays the
calibration test name and pass/fail status (for example, OFFS 1 PASS ).
When the calibration completes, a pass/fail message will be displayed.
If the calibration failed, then the calibration factors remain unchanged.
INFORMATION ABOUT CAL:TI QUIK? AND CAL:TI FINE?
CAL:TI QUIK? and CAL:TI FINE? are two different ways to calibrate out
the differences in electrical path length between Channel 1 and
Channel 2. When you provide the calibration signal, the instrument
measures how the difference in path length translates to an average delay
between the two channels.
The Quick Time Interval Calibration requires a simple input signal.
You provide on Channel 1 a clean square wave with a rapid rise time and
an approximate frequency of 10 MHz. The instrument routes the
calibration signal in COMMON to both channels 1 and 2, and measures
the average delay between the two channels so configured. The advantage
of the Quick Calibration is that it is easy, quick, and requires little special
equipment. The disadvantage is that the calibration term is best fit for
TI measurements configured COMMON and measured from rising to
rising edge; it leaves uncorrected a small systematic error for all other
configurations. The Fine Time Interval Calibration minimizes systematic
error by calibrating the instrument in each configuration.
2-10 Assembly-Level Service Guide