Spectrum Analyzer Mode Functions

%AI4

ON OFF

4LOCK ON OFF

+lOV REF DETECTOR

-1OV REF DETECTOR

determines the percent of amplitude modulation of the largest displayed signal and its two sidebands. The sidebands are assumed to be entirely from amplitude modulation. If there are differences in the sideband amplitude, the larger value is used. The measurement runs continuously, re-executing at the end of each sweep.

All three signals must be displayed. The frequency spacing of the sideband signals must be the same within the span accuracy of the measurement. All of the signals must be greater than the PEAK EXCURSION above the THRESHOLD. The amplitude scale may be either linear or logarithmic.

Front-Panel Key Access (jj)

turns off the analyzer phase locking. The counter is turned off so frequency correction is no longer done at the start of each sweep. Turning the phase locking off increases measurement speed, but it decreases frequency accuracy. This is a service diagnostic function and is for service use.

Front-Panel Key Access ICAL)

displays the output of the + 10 V reference from the A7 Analog Interface assembly as a horizontal line at the top graticule. This is a service diagnostic function and is for service use only.

Front-Panel Key Access (CAL)

displays the output of the - 10 V reference from the A7 Analog Interface assembly as a horizontal line at the bottom graticule. This is a service diagnostic function and is for service use only.

Front-Panel Key Access (CAL]

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