inserting signal with controllable time duration

[M.Hage]

For my experiment I need to generate a sinusodial singnal consisting
of 3 parts. Currently I am using a While procedere to switch between
two different sinusodial waveforms, but I can´t figure out a solution
to insert a 3rd signal between these two, as I´ld like to controll the
duration of this signal (duration time much smaller than 1 second). I
know this is pretty basic, but no one could help me yet. I would
really be gratful for any comment, hint or solution.

[Labviewguru]

Try downloading "Multitone Waveform example.vi" from NI's website. This allows for multiple waveforms, and may well be the solution you are looking for.