1. PAN
Movement of the camera in a horizontal direction.
2. PASSIVE
A non powered element of a system.
3. PEAK-TO-PEAK
The amplitude difference between the most positive and the most negative excursions of a signal.
4. PHOTODIODE
A two-electrode Iight-sensitive device in which the resistance between the two electrodes varies inversely with the amount of light falling on the lightsensitive surface.
5. PHOTOTRANSISTOR
A light-sensitive device with two or three electrodes.
6. PICO ou SURTO DE TENSÃO
Uma variação de amplitide em uma voltagem AC causado por descarga atmosférica, ou na rede elétrica primária.
7. POLARITY OF A PICTURE SIGNAL
The direction of the potential of a portion of the signal representing the dark area of a scene relative to the potential of a portion of the signal representing
the light of that same scene. Polarity is expressed as black negative or black positive.
8. POWER
The rate at which electrical energy is applied to or taken from a device. It is expressed in terms of watts, milliwatts, or microwatt.
9. PRE-EMPHASIS
A change in the level of some frequency components of a signal
10. PREAMPLIFIER
An amplifier which the primary function is to raise the output of a low-level source to an intermediate level so that the signal may be further processed
without appreciable degradation in the signal-to-noise ratio of the system.
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