An oscillator is a circuit that can generate a frequency source such as a sine wave, square wave or pulse train. An oscillator is fundamentally a combination of a frequency-sensitive circuit such as an LC circuit or a crystal and a negative resistance usually obtained by using an amplifier with positive feedback. Phase shift is the displacement of
Click here to download the full size of the above Circuit.
a waveform in time. For example, if a waveform is displaced by a complete wavelength. it is described as having a phase-shift of 360 °. If it is displaced by half a wavelength (i. e. 180 °) one wave will peak where the other is in a trough state and complete cancellation will result. If they are at any other angle of phase-shift, partial cancellation will result. A phase shift oscillator is a simple sine wave electronic oscillator. It contains an inverting amplifier, and a feedback filter which `shifts` the phase by 180 degrees at the oscillation frequency. The most common way of achieving this kind of filter is using 3 cascaded resistor-capacitor filters, at the oscillation frequency each filter produces a phase shift of 60 degrees and the whole filter circuit produces a phase shift of 180 degrees. Thus the total phase shift produced by the three RC networks is 180 °. Therefore at the specific frequency fo the total phase shift from the base of the transistor around the circuit and back to the base is 360 ° The mathematics for calculating the oscillation frequency and oscillation criteria for this circuit are surprisingly complex, due to each R-C stage loading the previous ones. The calculations are greatly simplified by setting all the resistors (except the -ve feedback resistor) and all the capacitors to the same values. In the diagram, if R1 = R2 = R3 = R, and C1 = C2 = C3 = C, then: The Hartley oscillator was invented...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: