The unit is simple to build, and does not need really low noise opamps, since they only act as a modulator oscillator. I used 1458 dual types in the prototype, and they are more than good enough. The transistors can be any low noise NPN type, and they are simply buffers, ensuring a high input impedance and low output impedance.
If the unit is to built into an amplifier, it may well be possible to leave out the input transistor, since a low impedance drive circuit is probably already available from an existing opamp. It may also be possible to leave out the second transistor if a high impedance input is available at the insertion point. This is somewhat unlikely, since the most common place to have the modulator is before the tone controls.
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The oscillator is a simple opamp feedback type, and produces a triangle wave from the capacitor (C3). This is amplified and buffered, and fed to the LED in the opto-coupler. If you are unable to obtain this device (made by Vactrol), use a high quality Lig
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....
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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....
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