OSCILLATEUR A CRISTAL DE QUARTZ

An oscillator assembly comprises an hermetically sealed housing having a plurality of parts 19, 22 of which at least the part 19 is made of quartz crystal or other piezo-electric crystalline material. Disposed within the housing is an oscillator 1c of quartz crystal material which is mounted on a planar support portion 19a of the housing part 19. This provides the oscillator 1c with a more secure support than in the prior art, and prevents distortion arising from different thermal coefficients of expansion. Oscillators and upper and lower housing parts may be formed in strips by etching, and assembled together before separation. The housing part 22 may also be of quartz or of metal or glass. The recessed housing part 19 may be formed in two pieces, a frame on a plate. Conductive film connections 20, 21 pass through the housing.