Free electronic circuit design and schematic diagram
This tone control circuit use very popular Baxandall configuration, a simple circuit configuration that provides boost and cut control in continuous manner. This circuit is very cheap to build, and it’s commonly implemented in commercial product. Here is the circuit’s schematic diagram: The transistors can be substituted by any general audio transistors with small current gain more than 100 (BC547, […]
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This audio power amplifier circuit is simple and robust, and use discrete component available on many electronic part stores. The final transistors use 2N3055 and MJE2055. Here is the circuit’s schematic diagram: The MJE2055 is an npn transistor, but the configuration with TIP42A make the whole combination of TIP42A and MJE2055 are seen as pnp transistor. This audio amplifier circuit […]
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Current handling capability of a power supply system often needed to be checked. Finding high power rated variable resistor to provide variable load testing might be difficult. There is wire wound type but it’s not always available at your local store, and the price and performance might be disappointing. This variable high power “resistor” uses 2N3055 power transistor to provide […]
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This voltage-controlled oscillator circuit is very compact and has a good linearity. The author said that the precision could be better than 0.01% If this circuit is properly constructed. Moreover, this circuit gives three different output waveforms: square, triangle, and sawtooth. This three waveform is important for music synthesizer and measurement devices. Here is the circuit’s schematic diagram: The oscillator […]
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Feedback in public address amplifier is something that should be avoided. The ideal solution is by adjusting the microphone and the speaker position, but it’s not always possible in many situation. Using frequency shifter to change the output frequency 10Hz lower than the input frequency can solve the problem, but it’s too expensive for a low cost public address system. […]
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Voltage to frequency is very useful in many situation, such as transmitting temperature measurement using standard voice radio transceiver. This circuit (see the circuit’s schematic diagram) uses only two CA3130 op-amps, but the performance is good enough. The linearity of the voltage-frequency transfer is better than 0.5% and the temperature coefficient is lower than 0.01% !! Assume that the output […]
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It’s easier to manage if we put the distortion and the compressor effect in one box. This Carlin fuzz compressor use unique method to give sustain and distortion effect in mixed circuit. Seem that the circuit do the dynamic compression and distortion in a single negative feedback loop. Here is the circuit schematic diagram: The dynamic compression is done by […]
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