DS0531SR-100.000MHZ DS0531SR40M DS0531SR-50.000MHZ DS0531SR-50MHz ds0531srce-10mhz DS0531SV(32.110MHZ) DS0531SV/24.5454MHZ DS0531SVL DS0531SVL(28.000MHZ) DS0531SVL(37.94331MHZ)