Free Simple Circuit Diagram
Frequency modulation (FM) can be used to transmit analog voltage level signal with good noise immunity. The transmission itself might employs different methods, and this circuit uses free air optical medium. This optical receiver circuit is built using a L14G2 detector, two stages of gain, and a FM demodulator. To obtain better sensitivity, we can use more stages of stabilized […]
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The frequency to voltage converter circuit illustrated in the schematic diagram below produces a 10 V output for 10 kHz full scale input (square waves or pulses). The simplicity of the circuit doesn’t mean a bad performance: this circuit has linearity about 0.06% at full scale. For your note, there is a trade-off between ripple versus response time. With Cfilter […]
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This is a linear FM detector circuit. This circuit usually is used in telemetry applications and wide range of analog communications. The main part of this circuit is a XR-2211. This circuit has an external buffer/amplifier that is needed due to the high-impedance output at pin 11 of XR-2211. This circuit also has a post-detection filter Rf/Cf. This circuit produce […]
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Below is figure of a transistor square-law detector. At a low quiescent collector current (95 uA), it biased to operate so the output will be significantly nonlinear. To test the circuit, we can feed base with a 550 kHz RF signal about 30% modulated with 1 kHz which is produced by the RF signal generator. The signal has peak to […]
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