
Sine wave oscillator can be implemented using Wien-Bridge oscillator like in our previous sine wave oscillator circuit, but now we present another method of generating sine wave signal. Using phase shifter, we can build a simple sine wave generator, as shown in the schematic diagram below: Sine wave oscillator using phase shifter has [...]
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Controlling the speed of three phase ac motor is done by controlling the frequency of the power line supply, since the motor is synchronized with the line frequency. Three phase ac motor speed controller is actually nothing more than three phase sine wave power inverter with variable frequency. The three phase power inverter is a [...]
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PLL oscillator is used to get very stable frequency woth very low distortion of sine wave output. The stability is equal to crystal-based oscillator, and the low distortion level of the sine wave output is equal to LC based oscillator. The method of PLL control in PLL oscillator is done by adjusting the frequency of [...]
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3D enhancement is needed to create a fully 3-dimensional sound for most stereo multimedia products. Usually, simple phase-delay circuits is used to produce a widening effect on the perceived sound field. However, there is transaural acoustic crosstalk effect. The following figure shows transaural acoustic crosstalk effect and schematic diagram of simple phase-delay circuits : [...]
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A phase control circuit can be used to control the power delivered to an AC load. The phase control circuit control the AC waveform, cutting the cycle to give full cycle, half cycle, zero cycle, or somewhere in between. You can say this circuit is similar to a dimmer circuit, but the switching is synchronized [...]
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This is a simple circuit for negative to positive supply logic level shifter. This circuit used to shift the logic level from minus to ground (such as MOS) to any logic level and from a plus to ground supply (such as TTL). Here is the circuit: This circuit uses the 2N3970 that provide [...]
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