An audio signal applied to VI is passed through the operational amplifier 741, U2. After being amplified, the output signal V2 is sampled and applied to a negative voltage doubler / rectifier circuit composed of diodes CRI and CR2, with the capacitor C1. The resulting negative voltage is used as a control voltage which is applied to the door] 2N54
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85 FET Q1. Capacitor C2 and resistor R2 form a filter for smoothing the voltage rectified audio control. The lFET is connected between pin 2 of the MC3340P grounded by a resistor of 1 kohm. As the voltage applied to the gate of FET] becomes more negative in magnitude, the channel resistance of FET] increases causing lFET to function as a voltage-controlled resistor. The MC3340P audio attenuator is the heart of the MCO. It is capable of 13 dB of gain or almost - 80 dB of attenuation as a function of external resistor placed between Pin 2 and ground. An increase in resistance decreases the gain from the MC3340P. The gain of the circuit is not entirely a linear function of the external resistance, but such behavior is similar across much of the gain / attenuation range. An input signal applied to the input of the AGC will cause the gate volt age the proportion lFET become negative. Accordingly, the JFET increases the resistance of the pin 2 to ground the MC3340P causing a reduction in gain. In this way, the AGC output is kept almost constant. source by next. gr
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....
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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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