BS 9612 N005:1977 Detail specification for cold welded seal quartz crystal units for oscillator applications. DN, DQ and DP enclosures, 0.8 to 20 MHz and 3.0 to 30 MHz frequency ranges. Fundamental thickness-shear mode, AT-cut, for operation over narrow temperature ranges (temperature controlled). Full assessment lev

standard by BSI Group, 06/15/1977