With a given sampling frequency, the number of samples that is taken determines the duration of the measurement. This number of samples is called record length. Increasing the record length, will increase the total measuring time. The result is that more of the measured signal is visible. In the images below, three measurements are displayed, one with a record length of 12 samples, one with 24 samples and one with 36 samples.

The total duration of a measurement can easily be calculated, using the sampling frequency and the record length:

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

Changing the record length of an instrument in the Multi Channel software can be done in various different ways:

• Right-clicking the instrument in the Object Tree, selecting Record length and then the appropriate value in the popup menu.
• Using hotkeys F11 and F12.
• Clicking the Record length label in the combined Record length + Sample frequency + Resolution indicator on the instrument toolbar and selecting the required value from the popup menu.
• Clicking the Record length indicator on the instrument toolbar and selecting the required value from the popup menu.
• Clicking the increase/decrease record length buttons and on the instrument toolbar.
• Right-clicking the horizontal scrollbar under the graph displaying signals from the instrument and selecting Record length and then the appropriate value in the popup menu.