Application of LFE SC-cut resonators at high stability oscillators

The LFE SC-cut resonators have some quite well known advantages. The main are: lack of electrodes in the active part of the crystal plate and very efficient suppression of B mode. Because of this application of LFE resonators can improve both long and short term frequency stability, critical for high stability oscillators parameters. A few models of different construction single side resonators were made and their parameters were measured. These resonators are very difficult to adjust (because of very low C1) so the special procedure of calibration using chemical treatment was developed. The especially optimized oscillation circuit was applied. Circuits and oven parameters were measured and discussed.