A frequency-adjustable oscillator suitable for digital signal clock synchronization comprises a SAW oscillator circuit for generating an analog controlled-frequency signal and a sinewave-to-logic level translator circuit in a double-sided package. The SAW oscillator circuit includes a tunable SAW resonator, a gain stage for energizing the SAW resonator, a voltage-variable control input for adjusting a frequency of the controlled-frequency signal, and a voltage-variable capacitive element operably linked to the SAW resonator and responsive to the control input. The sinewave-to-logic level translator circuit is operably linked to the SAW oscillator circuit and configured to generate a digital logic output signal having substantially the same frequency as the controlled-frequency output signal. The double-sided package includes a platform with sidewalls extending substantially upwardly to form a first cavity adapted to receive and electrically connect the SAW resonator and sidewalls extending substantially downwardly to form a second cavity adapted to receive and electrically connect at least one electronic component. A cover is coupled with the first cavity to create an isolated environment for containing the SAW resonator.