IEC TR 60444-4:1988 Measurement of quartz crystal unit parameters by zero phase technique in a pi-network. Part 4: Method for the measurement of the load resonance frequency fL, load resonance resistance RL and the calculation of other derived values of quartz crystal units, up to 30 MHz
Specifies a simple method of measuring load resonance frequency. The method uses the change in resonance frequency which occurs when a load capacitance is inserted in series with the crystal unit.