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An attenuator is a passive broadband electronic device that reduces the power of a signal without appreciably distorting its waveform. An attenuator is effectively the opposite of an amplifier, though the two work by different methods. While an amplifier provides gain, an attenuator provides loss, or gain less than unity. An attenuator is often ...
An eccentric rotary vane pump Another eccentric rotary-vane pump design. Note that modern pumps have an area contact between rotor and stator (and not a line contact). 1. pump housing 2. rotor 3. vanes 4. spring. A rotary vane pump is a type of positive-displacement pump that consists of vanes mounted to a rotor that rotates inside a cavity. In ...
In a microwave oven a waveguide transfers power from the magnetron, where waves are formed, to the cooking chamber. In a radar, a waveguide transfers radio frequency energy to and from the antenna, where the impedance needs to be matched for efficient power transmission (see below).
Figure 1. Waveguide slotted line. Slotted lines are used for microwave measurements and consist of a movable probe inserted into a slot in a transmission line.They are used in conjunction with a microwave power source and usually, in keeping with their low-cost application, a low cost Schottky diode detector and VSWR meter rather than an expensive microwave power meter.
At microwave frequencies, this material is usually a ferrite which is biased by a static magnetic field [1] but can be a self-biased material. [2] The ferrite is positioned within the isolator such that the microwave signal presents it with a rotating magnetic field, with the rotation axis aligned with the direction of the static bias field.
Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter , but such systems are expensive and generally used only in ...
Built-in variable optical attenuators may be either manually or electrically controlled. A manual device is useful for one-time set up of a system, and is a near-equivalent to a fixed attenuator, and may be referred to as an "adjustable attenuator". In contrast, an electrically controlled attenuator can provide adaptive power optimization.