Diode as a Rectifier

Historically, rectifiers using stacks of CU-CU2O plates were in use long before the mechanism of the Schottky barrier was understood. 

Full-wave rectifier using a bridge circuit. The bridge circuit provides positive voltage to the load regardless of the polarity of the source voltage. 

Diagram of a simple crystal receiver for AM broadcasts. The carrier frequency is picked up at the antenna and appears across the L-C tank circuit. The diode clips the negative half of the carrier waveform and the headphones respond to the amplitude of the audio waveform that was impressed on the carrier waveform. 

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