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Transistor Multivibrator

Author: Leonard Krugman


Fig. 6-4 (above). Transistor multivibrator.

Figure 6-4 illustrates the transistor equivalent of a basic multivibrator circuit. This configuration is generally useful in the frequency range of 5 to 15 kc. The parameter values shown are for an 8.33 kc oscillator which uses two Raytheon CK720 transistors. The frequency is determined by the RBCB time constant. The value of RB is limited to a maximum of about 200k ohms. CB is limited to a minimum of .002 μf. The frequency stability is poor compared to the types previously discussed. The output collector waveform is almost a perfect square wave. The advantages of the transistor multivibrator are its simplicity and the small number of components required.

Last Update: 2010-11-17