Tektronix WCA200A, User Manual

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Glossary
WCA230A & WCA280A User Manual
Glossary- 5
Load
Copy settings or other data from a file, but don’t maintain any connection
with that file.
Local Oscillator (LO)
An oscillator which produces the internal signal that is mixed with an
incoming signal to produce the IF signal.
Marker
A visually identifiable point on a waveform trace, used to extract a readout
of domain and range values represented by that point.
MAX HOLD
Digitally stored display mode which, at each frequency address, compares
the incoming signal level to the stored level and retains the greater level. In
this mode, the display indicates the peak level at each frequency after several
successive sweeps.
MIN HOLD
A spectrum analyzer feature which captures the minimum signal amplitude
at all displayed frequencies over a series of sweeps.
Modulate
To regulate or vary a characteristic of a signal.
Modulating Signal
The signal which modulates a carrier. The signal which varies or regulates
some characteristic of another signal.
Modulation
The process of varying some characteristic of a signal with a second signal.
Noise
Unwanted random disturbances superimposed on a signal which tend to
obscure it.
Noise Floor
The self-noise of an instrument or system that represents the minimum limit
at which input signals can be observed. The spectrum analyzer noise floor
appears as a “grassy” baseline in the display, even when no signal is present.
Open (Recall, Restore)
Bring data into the application from a file of application-native format.
OQPSK
Acronym for Offset QPSK (Quadrature Phase Shift Keying).
PDF
Acronym for Probability Distribution Function.