measurement bandwidth

The resolution bandwidth required for a specific EM1 measurement. For MIL-STD measurements, the resolution bandwidth is often determined by the tester with the approval of the contracting agency.

For commercial testing the measurement bandwidths required usually follow the recommendations of CISPR:

Band A (10 kHz to 150 kHz): 200 Hz

Band B (150 kHz to 30 MHz): 9 kHz

Band C and D (30 MHz to 1 GHz): 120 kHz

measurement range

The ratio, expressed in dB, of the maximum signal level that can be measured (usually the maximum safe input level) to the lowest achievable average noise level. This ratio is almost always much greater than can be realized in a single measurement. Refer also to dynamic range.

measurement units

Trace information is stored in trace arrays made up of measurement units. The measurement-unit range is restricted to integers between -32,768 and + 32,767. In a logarithmic scale, a measurement unit is one-hundredth of a dBm, or represented mathematically as: (value in dBm) x 100 = measurement units. As an example, - 10.115 dBm x 100 = -1012 measurement units, not -1011.5. Measurement units for linear-trace information are from zero, for the bottom of the display, to 10,000 for the top of the display, or the reference level.

memory

A storage medium, device, or recording medium into which data can be stored and held until some later time, and from which the entire original data may be retrieved.

memory card

A small, credit-card-shaped memory device that can store data or programs. The programs are sometimes called personalities and give additional capabilities to your instrument. Typically, there is only one personality per memory card. Refer also to personality.

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