LST EN 60689-2009 Measurement and test methods for tuning fork quartz crystal units in the range from 10 kHz to 200 kHz and standard values (IEC 60689:2008)
2009LST EN 60689-2009 Measurement and test methods for tuning fork quartz crystal units in the range from 10 kHz to 200 kHz and standard values (IEC 60689:2008)