Low Pass Filter Circuits: The Low Pass Filter Circuits of Fig. 15.7 is commonly used for low pass active filters. The filtering is done by the use of an RC network. The opamp is used…
Classification of Active Filters: An electric filter is often a frequency selective circuit that passes a specified band of frequencies and blocks or attenuates signals of frequencies outside this band. Classification of Active Filters are…
Types of Filters in Electronics: Types of filters in electronics may be of any physical form—electrical, mechanical, pneumatic, hydraulic, acoustical, etc. The most commonly used filters are of the electrical type. Types of filters in…
What are Passive Filters?: Passive filters are mainly networks using inductors, capacitors and resistors. The classical theory employed was based on the image parameter theory which in turn was based on the filter's characteristics and…
What is a Filter Circuit?: A network designed to attenuate certain frequencies but pass others without attenuation is called a filter. A filter circuit thus possesses at least one pass band, which is a band…
Synchronous Vibrator and Synchronous Chopper: Low dc current may be transformed into a high voltage dc by simple chopper action. Although an inductive type transformation process is required, the output dc may be obtained without…
Varactor Diode Symbol: A specially processed junction diode that assumes the properties of a variable capacitor (about 5 - 250 pf) when its dc reverse voltage is varied is called a Varactor Diode shown in…
Transistor Chopper Circuit: Transistor Chopper Circuit - A single transistor used as a dynamic switch to convert low level dc signal to an ac waveform is shown in Fig. 14.34. If the voltage applied to…
Diode Bridge Type Modulator with Transformer Coupling: Diode Bridge Type Modulator - Figure 14.33 shows a silicon diode ring modulator with an associated ac coupled dc amplifier. The amplifier itself has a gain of 65…
Magnetic Modulator: The most reliable substitutes for electromechanical choppers are magnetic modulators. These devices reach a null stability as low as 10 μV, but their response time is often less than 2 Hz and the…
