BI-METAL COMPENSATED CRYSTAL UNITS.
Abstract
Development work on two types of temperature compensated quartz crystal units is described. One type was a 5 MHz CR-1 size unit, the CR-(XM-62)/U, and the other was a 30 MHz HC-6 size unit, the CR-(XM-63)/U. In both cases compensation was achieved by using bimetallic elements to apply flexure stresses to the resonator plate. The development of the CR-(XM-62)/U was halted by a technical difficulty. But ten compensated units were fabricated and tested and frequency-temperature stabilities of +1.6 ppm over the range -40 C to +65 C were observed. Ten sealed CR-(XM-63)/U units were also fabricated and tested. Tolerances of + or - ppm were observed in these units over the range -20 C to +65 C. The majority of the units had a tolerance of + or - 2.5 ppm or better over the same range. Resistance to shock and vibration was satisfactory. Aging tests were inconclusive. Difficulties were encountered in obtaining resonator plates which had the desired ZZ' angle which reacted uniformly to external stresses. The basic repeatability of frequency-temperature curves over the range -40 C to + 90 C has been shown to be certainly less than + or - 0.2 ppm.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1965
- Accession Number
- AD0482864
Entities
People
- George R. Bart