I can't change the amplitude of the signal generator

figured out how to change DS203 waveform generator, but can not increase the amplitude of the signal? it’s about 3V, but I need more

Do you mean you can’t change the amplitude at all or you can’t raise it above 3v?

If the former then you need to say which firmware you are using.

If the latter then that is the limit of the hardware. The signal waveform is generated by a d2a converter and the supplies used are 3.3V.

If you need higher amplitudes then you will need an external amplifier.