Free electronic circuit design and schematic diagram
When we connect a mono audio output into a stereo headphone (simply by paralleling it), we would hear the sound with all of its components comes from one point, and the worst, that point is located inside your head. This perception is created by the fact that the signals from the right and left earphones have exactly the same amplitude […]
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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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This is a 3 Band Equalizer circuit. This circuit is made to control the treble, middle and bass range. This circuit uses a single op-amp. With single op-amp we can build equalizer which has three ranges, high frequency, mid frequency, and low frequency. Here is the schematic diagram of the circuit: This circuit has a cut off frequencies of 10kHz, […]
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This is a Variable Q Twin-T Notch Filter circuit. This circuit is used when low Q is needed. The Lower Q gives some advantages in rejecting the signal where the signal deviate slightly from the null of the notch network. The Q of this circuit can be adjusted from 0.3 to 50. This circuit has two voltage follower. The second […]
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This is a Bootstrapped Twin-T Notch Filter circuit. This circuit can generate high Q by combining the twin “T” with LM102 voltage follower. The generated Q is greater than 50. This circuit uses small capacitors since the LM102 uses the large resistance values in the “T”. Beside that, voltage follower also used as buffer that gives high input resistance of […]
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Below is a circuit that demonstrates one use of an OTA using an LM13600. Take a note that the strange symbol stand for OTA. In this circuit, negative feedback is employed which is low-pass filter whose corner frequency can be electrically adjusted. We can a filter that would tune from 2700 Hz to 9000 Hz approximately for the values shown. […]
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This a Sallen and Key Lowpass Filter circuit. This circuit is a second-order active filter. This circuit can be changed to highpass filter by interchanging capacitors and resistors. This circuit is featured with buffer. The buffer of this circuit is op-amp which configured in inverting configuration. This circuit is stable, since this circuit has positive feedback and never overcomes the […]
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