HARTLEY OSCILLATOR

Hartley¬† oscillator is a type of LC oscillator which is widely used as a local oscillator in radio receivers. Hartley oscillator was invented in 1915 by the American engineer Ralph Hartley. Figure shows the circuit diagram of a Hartley oscillator. It consists of single stage inverting amplifier and L-C phase shift network.¬† The phase shift …

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what is Multiplexing ? different techniques of multiplexing

Under the simplest conditions, a medium can carry only one signal at any moment in time. For multiple signals to share one medium, the medium must somehow be divided, giving each signal a portion of the total bandwidth. The current techniques that can accomplish this include frequency division multiplexing (FDM) time division multiplexing (TDM) Synchronous …

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How to install cctv camera – basic concept

CCTV is also called closed circuit television, it is now commonly used in retail shops, showrooms, malls , houses etc.. for security purpose. This article is used to provide a basic idea to know the installation of cctv camera. Components required for the installation are cameras, DVR/NVR, cables ( cat6 / coaxial), BNC connector, Power …

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Microwave antenna

Antennas are inductive.Microwave antennas are horn antenna, Parabolic antenna, slot antenna, dipole antenna, dielectric antenna, printed antenna, phase array antenna, Micro strip patch antenna, Plasma antenna, MIMO antenna. Horn antenna is the most widely used microwave antenna. As frequency increases gain of horn antenna also increases. Horn antenna is a fixed size antenna. Horn antenna …

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Micro wave link

Most of the link uses 4 and 6 GHz. Short term fading in microwave communication links can be overcome by diversity reception and transmission.Ionosphere propagation is not possible in micro wave communication because it penetrate through ionosphere. In microwave communication links, the rain drop attenuation experienced is mainly due to absorption of microwave energy by …

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