Figure 3. Experimental results of the proposed oscillator (a) variation of oscillation frequency with variable resistance R4 (b) a typical waveform generated by the circuit (1.984Hz, 2.5V p-p)

From

New Very Low Frequency Oscillator Using only a Single CFOA

D. K. Srivastava, V. K. Singh, R. Senani

American Journal of Electrical and Electronic Engineering. 2015, 3(1), 1-3 doi:10.12691/ajeee-3-1-1