Infra-red transmitter

Infra-red transmitter: It often happens that someone wants to watch television without the sound disturbing other people in the room. To avoid having a long cable trailing over the floor, the present transmitter (and accompanying receiver ) make it possible to listen to the TV sound wirelessly. The transmitter uses pulse-duration (=pulse-width) modulation. The modulated[…]

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Infra-red headphone receiver

Infra-red headphone receiver: This receiver is meant to complement the transmitter describe in the previous article. Its design is based on just one FET. This has the advantage that construction is simplicity ‘itself, and the disadvantage that for a sufficiently low output impedance the value of drain resistor R3 has to be fairly low. That results with[…]

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