Datasheet

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Mixed Domain Oscilloscopes

Two manual markers are also available for measuring non-

peak portions of the spectrum. When enabled, the reference

marker is attached to one of the manual markers, enabling

delta measurements from anywhere in the spectrum. In addi-

tion to frequency and amplitude, manual marker readouts also

include noise density and phase noise readouts depending on

whether Absolute or Delta readouts are selected. A “Refer-

ence Marker to Center” function instantly moves the frequency

indicated by the reference marker to center frequency.

Automated peak markers identify critical information at a glance. As shown here,

the ve highest amplitude peaks that meet the threshold and excursion criteria

are automatically marked along with the peak’s frequency and amplitude.

Spectrogram

The MDO4000C Series with option SA3 or SA6 includes

a spectrogram display which is ideal for monitoring slowly

changing RF phenomena. The ×-axis represents frequency,

just like a typical spectrum display. However, the y-axis repre-

sents time, and color is used to indicate amplitude.

Spectrogram slices are generated by taking each spectrum

and “ﬂipping it up on its edge” so that it’s one pixel row tall,

and then assigning colors to each pixel based on the ampli-

tude at that frequency. Cold colors (blue, green) are low

amplitude and hotter colors (yellow, red) are higher amplitude.

Each new acquisition adds another slice at the bottom of

the spectrogram and the history moves up one row. When

acquisitions are stopped, you can scroll back through the

spectrogram to look at any individual spectrum slice.

Spectrogram display illustrates slowly moving RF phenomena. As shown here, a

signal that has multiple peaks is being monitored. As the peaks change in both

frequency and amplitude over time, the changes are easily seen in the Spectro-

gram display.