| 摘要 |
PURPOSE:To make it possible to detect the resonance frequency of a TM vibrator, by a method wherein the output of a white noise oscillator is applied to two TM vibrators and the outputs thereof are amplified to be inputted to two BPFs while the outputs thereof are taken out. CONSTITUTION:The output signal of a white noise generator 10 is inputted to two vibrators (each being a TM vibrator) each having resonance frequency. When the output signals of the vibrators 1 are inputted to BPF 12, 13, the filtered signal is a detection signal. The TM vibrators 1 operate as filters having two peaks in resonance frequency and generate signals having power spectra as shown by drawings. Because these signals each is bad in an SN ratio, they are passed through an amplifier 11 and BPF 12, 13 to cut frequency components other than resonance frequency and a signal (d) having a power spectrum is outputted. As the result, the measurements of the greater number of the TM vibrators can be simultaneously and instantaneously performed. |
