scale factor

The per-division calibration of the vertical axis of the display.

scan (frequency span) linearity

The measured accuracy of the horizontal axis of the analyzer display. When two horizontal points are set with analyzer controls, then measured, the linearity is the calculated error between the two points compared with the analyzer settings.

selectivity

See bandwidth selectivity.

sensitivity

The level of the smallest sinusoid that can be observed on an analyzer, usually under optimized conditions of minimum resolution bandwidth, 0 dB input attenuation, and minimum video bandwidth. Hewlett-Packard deEnes sensitivity as the displayed average noise level. A sinusoid at that level appears to be about 2 dB above the noise.

serial prefix

Serial numbers that identify an instrument begin with a five-character prefix. The prefix in this case represents the version of firmware that particular instrument was shipped with. For HP 70000 Modular Measurement Systems, file numbers saved by the user in memory are preceded with letters that define the file type. Refer to the HP 70000 system operation manual for detailed information.

shape factor

Refer to bandwidth selectivity.

signal resolution

The ability of the analyzer to resolve two separate input signals. Closely spaced signals are more difficult to resolve than signals spaced far apart. Refer also to resolution bandwidth and shape factor.

signal identification

A routine that identifies whether or not a particular Fourier transform response on the analyzer’s display is at the correct frequency. The displayed signal may be aliased by the FFT calculation because of inadequate sample rate. The signal identiEcation routine indicates if the signal is being displayed at the wrong frequency.

Glossary-23