The Wien-Bridge oscillator fulfills these requirements because there is a low pass filter, a high pass filter and a 180 deg. phase shift from the feedback networks from the input to output. This totals 360 deg. to start the circuit oscillating. If all three of the criteria are met and you have a resonant Grequency under 1 MHz, then you have a cir
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cuit that produces a Sine Wave from a DC power source. The second stage of our Function Generator is this Schmitt Trigger. This circuit is used to convert a Sine Wave into a Square Wave. This happens because the input signal is large enough to pass through both the lower and the upper voltage trip points. This is possible when the upper part of the Sine Wave hits the output voltage. The voltage will go directly to +Vsat and stay there until the lower peak causes it to go to -Vsat add infinitum. This circuit produces a "ramp" voltage. Normally you would have just a capacitor in the negative feedback loop. But because we want no output offset voltage, we had to put a resistor in parallel with the cap. Besides limiting the output offset, it produces our "Virtual Ground. " This virtual ground is created by the 741`s very high input impedance. About 150 M*`s of it. What happens is the input resistor is connected to the positive input and a resistor coming from the output signal is connected also to the +in. Total current will go through the first resistor and split towards the second resistor because it`s an easier path to ground. When this is set up like this, as long as both resistors are less than 150 Megs, a ratio situation occurs between them. Depending on the ratio, or Gain created, you can control how much amplification it has. Now throe in the cap and a Saw Tooth wave shape is created. In conclusion, the 741 Op Amp can...
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.....
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