HP 54501A Service Manual page 14

FIP 54501A GENERAL INFORMATION
Table 1-2. HP 54501A Operating Characteristics (continued)
Display Modes (continued)
Variable persistence : The time that each data
point is retained on the display may by varied from
200 ms to 10 seconds, or it may be displayed
infinitely .
Averaging : The number of averages, (n) may be
specified in powers of 2, up to 2048 . On each ac-
quisition, 1 /n times the new data is added to
(n-1)/n of the previous value at each time coor-
dinate . Averaging operates continuously, except
for the HP-IB DIGITIZE command, for which
averaging ierminates al a user-specified number of
averages .
Envelope : Provides a display of the running max-
imum and minimum voltage levels at each horizon-
tal position of a repetative waveform .
Graticules : The user may select full grid, axes,
frame, or no graticule .
Connect-the-dots : Provides a continuous display,
connecting the sample points with straight lines .
Connect-the-dots is operative for modes in which a
single valued waveform can be connected, includ-
ing AVERAGE, ENVELOPE, and MINIMUM
PERSISTENCE modes .
Scroll mode : The HP 54501A automatically selects
scroll mode at time-per-division settings from 200
ms/div to 5 s/dlv if the scope is in AUTO mode, or
If the scope Is in TRIGGERED mode with the delay
at the left edge of the display set is greater than or
equal to 0 . Scroll mode updates each data point
on the displayed waveform as the data is acquired .
DELTA V / DELTA t Markers : dual voltage markers
and dual time markers are provided . Voltage
markers may be independently assigned to chan-
nels, memories, or functions .
AUTOMATIC PARAMETRIC MEASUREMENTS
Automatic Pulse Parameter Measurements : The
HP 54501A performs 16 automatic pulse parameter
measurements from the front panel and additional
measurements via HP-IB including ALL,
OVERSHOOT, and PRESHOOT . The standard
measurements are performed with 10%, 50%, and
90% voltage thresholds, as defined by IEEE
Standard 194-1977, "IEEE Standard Pulse Terms
and Definitions" .
User-definable Measurement Thresholds : The HP
54501 A lets you set your own thresholds for auto-
matic measurements . Both the upper and the lower
thresholds may be set from 0% to 100% as long as
the upper threshold value is greater than or equal
to the lower threshold . The mid threshold is always
equal to the mid-value between the upper and
lower threshold .
Continuous measurements: may be turned,on or
off . With continuous measurements off, the voltage
and time markers are placed on the waveform to
indicate where the measurement is taken .
Measurement Statistics: The maximum, minimum,
average, and most recent of continuously updated
measurements are calculated and displayed . Any
three measurements may be selected .
Measurement Limit Test: Maximum and minimum
limits may be set for three of the automatic
measurements . These continuously updated
measurements are compared to the maximum and
minimum limits . If the measurements are found to
be outside the defined limits, the acquisition is
stopped and the waveform can be stored to a
memory or the screen can be sent to a printer . In
addition, an HP-IB Service Request can be
generated, so a controller can be flagged to
request the waveform and the measurement infor-
mation via HPAB .
SETUP AIDS
Autoscale : Pressing the Autoscale button auto-
matically adjusts the vertical and horizontal deflec-
tion factors as well as the trigger level for a display
appropriate to the signals applied to the inputs .
The Autoscale feature requires a signal with a duty
cycle greater than 0 .5% and a frequency greater
than 50 Hz .