Stanford Research Systems SR780, Operating Manual And Programming Reference

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4-12 Octave Frequency Menu
SR780 Network Signal Analyzer
Octave Frequency Menu
When the Measurement Group is Octave Analysis, this menu selects the number and
spacing of frequency bands for the active display. See ‘Octave Analysis’ in Chapter 2 for
a discussion about octave analysis fundamentals.
Highest Band
Set the Highest Band for the active display. The limits for the Highest Band are
determined by the Octave Resolution and the number of Octave Channels.
1 Octave Channel
1/1 Octave:
[125 mHz .. 32 kHz]
1/3 Octave: [160 mHz .. 40 kHz]
1/12 Octave: [190 mHz .. 12.34 kHz]
2 Octave Channels
1/1 Octave:
[125 mHz .. 16 kHz]
1/3 Octave: [160 mHz .. 20 kHz]
1/12 Octave: [190 mHz .. 6.17 kHz]
The total power of all measured bands is displayed as a filled in band at the right side of
the graph.
The exact band center frequencies are calculated according to the ANSI standard. The
displayed frequencies are sometimes rounded to even values for a simpler display.
The measurement may span 1 to 11 octaves. Increasing the Highest Band will also
increase the Lowest Band if necessary to keep the measurement span at 11 octaves.
The two displays can have different Highest Bands. This entry field can be linked to both
displays using the [Link] key. Linking is only allowed if both displays have the same
Octave Resolution.
Command: OHIB (?) d {, f}
Lowest Band
Set the Lowest Band for the active display. The limits for the Lowest Band are
determined by the Octave Resolution.