Sinusoidal Oscillators

Negative Resistance Oscillators – Working and Types: Negative resistance oscillators make use of negative resistance elements such as tetrodes, tunnel diodes, unijunction transistors etc. There are two types of negative resistance oscillators, which are commonly used for high frequency generation. These are dynatron and tunnel diode oscillators. Dynatron operates in the negative resistance region of

Crystal Oscillators – Circuit, Working, Advantages and Disadvantages: In crystal oscillators, the usual electrical resonant circuit is replaced by a mechanically vibrating crystal. The crystal (usually quartz) has a high degree of stability in holding constant at whatever frequency the crystal is originally cut to operate. The crystal oscillators are, therefore, used whenever great stability

Hartley Oscillator using Transistor Analysis: The transistor Hartley oscillator is as popular as Colpitt’s oscillator and is widely used as a local oscillator in radio receivers. The circuit arrangement is shown in Fig. 21.16. Hartley oscillator circuit is similar to Colpitt’s oscillator circuit, except that phase shift network consists of two inductors L1 and L2

Clapp Oscillator – Circuit Diagram and Operation: The Clapp oscillator shown in Fig. 21.15 is a refinement of the Colpitt’s oscillator. The single inductor found in the Colpitt’s oscillator is replaced by a series L-C combination [See L and C3 in Fig. 21.15]. Addition of capacitor C3 in series with L improves the frequency stability

Colpitts Oscillator using Transistor Circuit: The Colpitts oscillator circuit is a superb circuit and is widely used in commercial signal generators up to 100 MHz. The basic Colpitts Oscillator using Transistor circuit is shown in Fie. 21.13(a). It basically consists of a single stage inverting amplifier and an L-C phase shift network, as obvious from the

Franklin Oscillator Circuit Diagram: A simple L-C oscillator, called the Franklin oscillator and its circuit diagram is shown in Fig. 21.12. Here two CE amplifier stages are employed to provide 360° phase shift from input to output. The values of the different components used in the circuit are chosen to provide overall loop gain of the

Tuned Base Oscillator – Definition and Working Principle: When a parallel tuned L-C circuit is placed in the base-to-ground circuit, the oscillator is known as the tuned base oscillator. The basic circuit of a tuned base oscillator is shown in Fig. 21.11. The tuned base oscillator circuit is also named as the tickler oscillator or

Tuned Drain Oscillator – Circuit Diagram and Equation: Tuned drain oscillator is similar to the tuned collector oscillator, and the basic circuit is given in Fig 21.10. Because of its high input impedance and high voltage gain, an FET can be used to build up very simple and efficient oscillator circuit. The frequency of oscillation

Tuned Collector Oscillator – Definition, Working and Equation: The basic circuit of a tuned collector oscillator is shown in Fig. 21.7. It is called the tuned collector oscillator, because the tuned circuit is con­nected to the collector. The tuned circuit, con­stituted by the capacitor C and transformer pri­mary coil L, forms the load impedance and