Free electronic circuit design and schematic diagram
With the circuit shown in the following schematic diagram, both channels of this stereo preamp is constructed using RCA CA3052 quad AC amplifier. this pre-amplifier circuit is featured with tone control (bass – treble). Make a similar circuit to complete the other channel, since the circuit for left and right channel are similar. To be high-fidelity, total harmonic distortion should […]
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Small audio amplifier is useful for audio troubleshooting or simple audio projects. It should be a low cost and easy to build. Using integrated circuit for this purpose is the right choice. With LM380 audio amplifier integrated circuit, 2 Watts power can be delivered. For better thermal endurance, a large copper track can be printed in the board to provide […]
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This simple but complete Theremin circuit is constructed using only two inverter chip plus one regulator IC. This Theremin circuit consist of five functional blocks: power supply regulator, hand controlled oscillator, null oscillator, mixer, and filter. Here is the complete schematic diagram: Voltage Regulator and Circuit Protector The power supply regulator consist of LP2950 regulator IC, which stabilize […]
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Normally, Theremin works by detecting hand proximity using capacitive coupling method. A Theremin circuit shown in the schematic diagram below use different method to control the pitch. The oscillator of this tone generator, both the volume and frequency are controlled using LDRs, a light sensitive electronic component, so we can call this circuit an optical Theremin. Look at the following […]
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Theremin circuit shown in this schematic diagram uses digital component, so we can call it a digital Theremin. This circuit employs logic inverter 74C04 or CD4069 hex inverter and CD4046 phase-locked-loop (PLL) IC. The CD4069 logic inverter is operated as a fixed-frequency oscillator with frequency around 100kHz. The CD4046 is operated as a variable frequency oscillator which is adjustable around […]
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This schematic diagram show a single chip Theremin circuit. Theremin is an electronic music instrument which sense hand movement to control the tones/frequency. This Theremin circuit uses two separate Colpitts LC oscillators to produce a beat frequency. The frequencies of two Colpitts LC oscillators are mixed and then rectified. This rectification demodulate the mixed signal to get the beat frequency […]
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This is a 22-W Amplifier circuit that is designed for or 12-V DC power supply Systems. There are many application for this circuit, such as in car audio application. In car electrical power supply system, the 12V power supply will be provided by the host vehicle’s battery. The capacitor C3 is used to give ripple rejection, since noisy power supply […]
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