The Oscillatory frequency is extremely constant irrespective of temperature or source voltage fluctuations about a wide selection. Because it seems the output is somewhere around 3V ptp on square wave, and 2V r.m.s. from the sine -wave. A switched attenuator may speedily be provided if you'd like to be gentler https://nricnumbergenerator94330.azuria-wiki.com/1294959/5_simple_statements_about_generate_nric_singapore_explained