HP 8591C, Руководство пользователя, Страница: 343 / 373

limit line
A test limit made up of a series of line segments, positioned according to
frequency and amplitude within the analyzer’s measurement range. Two
defined limit lines may be displayed simultaneously. One sets an upper
test limit, the other sets a lower test limit. Trace data can be compared
with the limit lines as the analyzer sweeps. If the trace data exceeds
either the upper or lower limits, the analyzer displays a message or
sounds a warning, indicating that the trace failed the test limits.
limit-line file
The user-memory Ele that contains the limit-line table entries. Limit lines
are composed of frequency and amplitude components that make up a
trace array and this data is stored in the Ele. The limit-line Ele feature is
available on analyzers that are capable of limit-line operation. Refer also
to limit line.
limit-line table
The line segments of a limit line are stored in the limit-line table. The
table can be recalled to edit the line segments, then restored in the
limit-line
Refer also to limit line.
log display
The display mode in which vertical deflection is a logarithmic function of
the input-signal voltage. Log display is also referred to as logarithmic
mode. The display calibration is set by selecting the value of the top
graticule line (reference level), and scale factor in volts per division. On
Hewlett-Packard analyzers, the bottom graticule line represents 0 volts for
scale factors of 10 dB/division or more. The bottom division, therefore, is
not calibrated for those analyzers. Analyzers with microprocessors allow
reference level and marker values to be indicated in
volts, and occasionally in watts. Nonmicroprocessor-based analyzers
usually offer only one kind of unit, typically
marker
A visual indicator we can place anywhere along the displayed trace. A
marker readout indicates the absolute value of the trace frequency and
amplitude at the marked point. The amplitude value is displayed with the
currently selected units.
maximum input level
The maximum signal power that may be safely applied to the input of an
analyzer. Typically 1 W (-30
for Hewlett-Packard analyzers.
Glossary- 10