Circuitry, electronic signal

Most television screens are part of a cathode ray tube. As you know, a cathode ray tube is an evacuated chamber which produces a beam of electrons, known as a cathode ray. Electronic circuitry inside the television processes an electronic signal received from the television station. The processed signal is used to vary the strength of several electron beams, while magnetic fields are used to direct the beams to different parts of the screen. 

Most detectors depend on the photoelectric effect, where incident light (photons) liberates electrons from a metal or other material surface. Some sort of external circuitry collects these electrons and measures their number as current. The current is then proportional to the light intensity and therefore a measure of it. Important requirements for a detector include (i) high sensitivity to allow the detection of low levels of radiant energy, (ii) short response time, ffW)long term stability, and (iv) an electronic signal which is easily amplified for typicsd readout apparatus. 

Perhaps you have just purchased a new electronic device, such as a personal computer, video camera, pager, or cell phone. The advanced circuitry in such devices can malfunction in humid environments. Moisture can reroute and even short circuit electric signals, impairing the operation of your new electronic equipment. Manufacturers recognize that moisture can adversely affect their products and... 

Even conventional hotplates can be fitted with a continuously variable temperature control thanks to platinum thin-film sensors. The encapsulated platinum sensor is positioned so that it is in contact with the cast iron plate from below and thus able to register the temperature of the hotplate. Normally the power supplied to the plate is regulated by a stage switch. The increased control sensitivity is made possible by incorporating electronic circuitry capable of interpreting and acting upon the sensor signals. 

The actual mode of connection between instrument and computer varies depending on the type of signal generated and the design of the instrument. The connection can be made via a serial port, a parallel port, or a USB port. The electronic circuitry required is built into the instrument s internal readout electronics or into an external box used for conditioning the instrument s output signal. In some cases, the instrument will not operate without the computer connection and is switched on and off as the computer is switched on and off. In other cases, the entire computer is built into the instrument. 

Since 1945 an increasing understanding of the phenomenon of cavitation has developed coupled with significant developments in electronic circuitry and transducer design (i. e. devices which convert electrical to mechanical signals and vice versa). As a result of this there has been a rapid expansion in the application of power ultrasound to chemical processes, a subject which has become known as Sonochemistry . 

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