# How to tune the radial mode vibration of a PZT disc transducer?

I am trying to create a set-up where I can radially vibrate a 1x1 cm sample using a piezoelectric disc transducer. I know that at the $f_{min}$ of a PZT transducer, for the disc geometry, there is a radial vibration. How can I tune this vibration if I want to vibrate my sample radially at different frequencies?