[Discuss-gnuradio] How to set the time (y) axis duration (as desired) for the waterfall sink?

Hi,

Can the time axis (y-axis) of the qt-gui waterfall sink be set as desired? By default, it only shows a duration of 20 seconds. I would like this to be adjusted,  for example, to 1 minute or two minutes, etc.

I'm compiling the waterfall sink directly from C++ (I'm not using python or GRC).

Thanks in advance.

Regards,

khalid