The present invention offers useful ways of achieving high temperature stability of frequency determining components in temperature stabilized frequency control devices such as, for example, oven-controlled frequency reference devices.

The present invention offers novel ways of achieving high degree of mechanical stress isolation and high accuracy of temperature sensing in quartz crystal resonators.

A quartz crystal resonator comprises an orthogonally mounted doubly rotated QAS-type resonating element having a pair of bridges positioned at a defined angle in relation to the resonating element's ZI or XI axes. The resonator has reduced sensitivity to mechanical acceleration.