Free electronic circuit design and schematic diagram
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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