Measurement 9: Performing a triggered measurement (e.g. balloon burst, or pistol shot)

WinMLS can be used to record the response from a transient signal, such as a hammer strike, balloon burst or pistol shot.

Go to Measurement->Settings… and select the Scope Mode/Data Acquisition settings shown below. We use this measurement mode since we will only record data.

Then turn off the generator by making sure  is not checked. Then set the input signal type to Transient as shown below.

Now click the  button to display the whole dialog and make sure  is checked.

In the example figure above the trigger level is set to –30 dBFS. This means that WinMLS starts measuring when the input signal is -30 dB below the full scale input level (full scale is the higest possible level, above this level digital clipping starts).

The Pre-trigger duration shown above determines how many milliseconds before the trigger level is reached we want to include in the measurement.

The Pre-record duration shown above is set to 200 to avoid that the trigging should start in case the sound card should give a pulse when recording is starting (this may happen with some sound cards).

Note: In the left part of the Status Bar (positioned at the bottom of the WinMLS program) shown above you will be notified when the measurement starts.