Hello g0s,
There are a few ways to load a custom waveform for the VSG. I know you don’t want to use the application we provide, but the easiest way is to use the UI to load the custom waveform file. There are example waveform files in the application directory at
C:\Program Files (x86)\Signal Hound\VSG25\arb_examples
You can also use the C programming interface we provide, the files for which are also provided in the application directory at
C:\Program Files (x86)\Signal Hound\VSG25\api
You will want to use the sgSetFrequencyAmplitude and sgSetCustomIQ functions to achieve this.
Waveforms can be created in excel or a number of other ways, common ways might be using a math library such as Matlab, etc.
Let us know if you have more specific questions.
Regards,
Andrew