Stanford Research Systems SR780, Operating Manual And Programming Reference

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Octave Analysis 1-27
SR780 Network Signal Analyzer
Use the knob to select (Twelfth) and press
[Enter].
Choose 1/12 octave bands.
Each band represents 1/12 of an octave with very
good frequency resolution.
Note that the measurement requires a long settling
time. Narrow bands increases the settling time
(1/bandwidth).
Choosing narrow bands also increases the number
of calculations required and decreases the
maximum frequency which can be measured.
7. Press <Octave Resolution>
Change the number of bands per octave again.
Use the knob to select (Third) and press [Enter].
Let’s return to 1/3 octaves.
Press <Highest Band>
Change the highest measured band.
Remember, changing the octave resolution has
lowered the highest band in the measurement.
Use the knob to select 20 kHz and press [Enter].
Set the highest band to 20 kHz.
This is the highest allowed band for 2 channel, 1/3
octave analysis.
Press <Octave Channels>
We can change the number of channels which are
being measured.
Use the knob to select (1 Channel) and press
[Enter].
Choose single channel octave analysis. In this case,
both displays will always have the same input,
resolution, frequency range and averaging.
They can differ in their display related parameters,
such as view and scaling.
Press <Highest Band>
Change the highest measured band.
Single channel analysis has twice the measurement
bandwidth of two channel analysis. Thus, to
increase the highest measured band, use 1 channel
analysis.
Use the knob to select 40 kHz and press [Enter].
Set the highest band to 40 kHz.
This is the highest allowed band for 1 channel, 1/3
octave analysis.