The combination of sampling frequency and record length forms the time base of an oscilloscope. To setup the time base properly, the total measurement duration and the required time resolution have to be taken in account.

There are several ways to find the required time base setting. With the required measurement duration and sampling frequency, the required number of samples can be determined:

record length in samples = Measurement duration in seconds * sampling frequency in Hz

With a known record length in samples and the required measurement duration, the necessary sampling frequency can be calculated:

sampling frequency in Hz = record length in samples / Measurement duration in seconds

In the Multi Channel software, both record length and sampling frequency can be set independently, to give the best flexibility. They can be selected from menu's, using toobar buttons but also keyboard short cuts are available, for more information, refer to:

• sample frequency
• record length

The Multi Channel software also provides controls to change record length and sample frequency simultaneously to specific combinations to obtain certain time/div values:

• Clicking the Time/div indicator on the instrument toolbar and selecting the required time/div value from the popup menu.
• Clicking the increase/decrease Time/div buttons and on the instrument toolbar.