Patent ID: 8248174

Claim:
An oven controlled crystal oscillator for surface mounting comprising: a flat first substrate made of ceramic which is quadrangular in plan view and on which are installed at least a surface mounted crystal device having mounting terminals on the outside bottom surface and a heat resistor; and a second substrate made of a glass epoxy resin which is quadrangular in plan view and which faces said first substrate in alignment in the length direction and the width direction and has a larger external shape in plan view than said first substrate, wherein said second substrate has an opening into whose center said crystal device is inserted, said crystal device has terminal sections at four locations corresponding to the surface outer periphery of said first substrate where said crystal device is installed and the peripheral surfaces of the opening in said second substrate, and the terminal sections of said first substrate and second substrate are electrically and mechanically connected by solder; wherein a front end side head section of said crystal device inserted into the opening section of said second substrate is positioned inside the open surface of said opening section, and from terminal sections provided at four locations on said second substrate, conductive paths extend via the outside surface of said second substrate to external terminals formed on the outside bottom surface.