Glossary

Color Difference Signals Signals used by color television systems to convey color information in such a way that the signals go to zero when there is no color in the picture. R-Y, B-Y, I, and Q are all color difference signals for the NTSC system; U and V are color difference signals for the PAL system.

Component Video Video which exists in the form of three separate signals, all of which are required in order to completely specify the color picture. For example, R, G, and B; or Y, R-Y, and B-Y.

Composite Video A single video signal containing all of the necessary information to reproduce a color picture. Created by adding quadrature amplitude modulated R-Y and B-Y to the luminance signal for NTSC systems or U and V to the luminance signal for PAL systems.

CW Continuous Wave. Refers to a separate subcarrier sine wave used for synchronization of chrominance information.

dB (Decibel) A decibel is a logarithmic unit used to describe signal ratios. For voltages, dB = 20 Log10 (V1/V2).

DC-CoupledA connection configured so that both the signal (AC component) and the constant voltage on which it is riding (DC component) are passed through.

DC Restorer A circuit used in picture monitors and waveform monitors to clamp one point of the waveform to a fixed DC level.

Demodulator In general, this term refers to any device which recovers the original signal after it has modulated a high-frequency carrier. In television it may refer to:

(1)An instrument, such as a TEKTRONIX 1450, which takes video in its transmitted form (modulated onto the picture carrier) and converts it to baseband.

(2)The circuits which recover R-Y and B-Y for NTSC systems or U and V for PAL systems from the composite signal.

1740A/1750A Series Waveform/Vector Monitor User Manual

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