HP HP 8712ET, User Manual, Page: 146 / 480

4-28 ET User’s Guide
Using Instrument Functions
Using Limit Testing
Using Limit Testing
Limit testing is a measurement technique that compares measurement
data to constraints that you define. Depending on the results of this
comparison, the analyzer can indicate if your device either passes or fails
the test.
Limit testing is useful for real-time tuning of devices to specifications.
When limit testing is turned on, pass/fail results can be output to the
display and also to the LIMIT TEST TTL IN/OUT connector on the rear
panel. See
Figure 7-2 on page 7-4 for more information.
Limit testing is implemented by creating individual flat, sloping, or
single point limits on the analyzer display. These types of lines may be
used individually or combined to represent the performance parameters
for your device under test. Also available are limit testing capabilities for
five types of marker searches: statistical mean, peak-to-peak ripple,
flatness, delta amplitude, and delta frequency.
NOTE Limit testing is only performed on the measurement data trace. It cannot
be performed on a memory trace.
NOTE Limit line testing is not available when the analyzer is in Smith chart or
polar format. If limit lines are on and you change to Smith chart or polar
format, the analyzer will automatically turn off the limit line(s).
The following examples are performed using a transmission
measurement of the bandpass filter shipped with your instrument. To
follow along with these examples, connect your filter to the analyzer and
press:
PRESET
FREQ
Center 175 MHz
Span 200 MHz
SCALE 5
Enter
Reference Level
−
15 Enter