Mosquitolessexploring options in mosquito killers, repellents, and control

Does anyone know how to get the ringtone that adults can not hear?

the ringtone that you can hear adolescents is also call Mosquito noise

This would have to be very sharp (probably more than 25,000 cycles per second). Phone speakers are capable of generating a degree so high? Probably not, since it would raise the cost of the phone a lot.