Tektronix 2715, User Manual

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Glossary
Glossary–8
2715 User Manual
Phase Lock
The control of an oscillator or signal generator so as to operate at a constant
phase angle relative to a stable reference signal source. Used to ensure
frequency stability in spectrum analyzers.
Primary Controls
Those controls of fundamental importance to spectrum analyzer operation:
frequency control, span/div, and reference level.
Primary Marker
The marker displayed in the Single Marker mode whose frequency and/or
position is changed when tuning with the CENTER/MARKER FREQUEN-
CY control. When two markers are displayed, the brightest marker is the
primary marker.
Pulsed Carrier Waveforms
Signal types wherein the carrier is turned on and off, or pulsed, as in radar,
sonar, and continuous wave (CW) code.
Pulse Stretcher
A pulse shaper that produces an output pulse, whose duration is greater than
that of the input pulse, and whose amplitude is proportional to that of the
peak amplitude of the input pulse.
Reference Level
The signal level required to deflect the CRT display to the top graticule line.
Relative Display Flatness
The display flatness measured relative to the display amplitude at a fixed
frequency within the frequency span, expressed in decibels.
Residual FM (Incidental FM)
Short term displayed frequency instability or jitter due to instability in the
spectrum analyzer local oscillators. Given in terms of peak-to-peak
frequency deviation and expressed in hertz or percent of the displayed
frequency.
Residual Response
A spurious response in the absence of an input signal. (Noise and zero pip
are excluded.)
Resolution Bandwidth (RBW)
The width of the narrowest filter in the IF stages of a spectrum analyzer. The
RBW determines how well the analyzer can resolve or separate two or more
closely spaced signal components.
Save
A function which inhibits storage update, saving existing data in a section of
multiple memory (for example, Save A).