IEC 60510-3-3:1988 pdf download

IEC 60510-3-3:1988 pdf download.Methods of measurements for radio equipment used in satellite earth stations Part 3: Methods of measurement for combinations of sub-systems Section Three — Measurements for monochrome and colour television transmission.
IEC 60510-3-3 deals with methods of measurement for monochromc and colour television transmission. These measurements are additional to the measurements in the baseband given in Part 1, Section Four (IEC Publication 510-1-4). which are common to telephony and to television, e.g. group-delay and amplitude/frequency charactcristics.
The CCIR Recommendations and Reports which describe test waveforms appropriate to the various television systems in current use are listed in the references given in Clause 9.
2. Introduction
Suitable commercial measuring equipment is generally available, hut it is important to ensure that its performance is adequate for carrying out the tests to be described. For example, oscilloscopes should exhibit a flat frequency response and a good return loss (e.g. 30 dB) to at least the upper nominal frequency limit of the video baseband.
The test signals called for in this section shall be applied to the system under test at nominal level unless otherwise stated. Nominal system input level is that level which produces the nominal frequency deviation in accordance with reference (I] (see Clause 9).
4. Signal polarity and d.c. component
4.1 Definition and general considerations
The polarity of the video signal is defined as positive when a black-to-white transition is accompanied by an increase in voltage of the luminance signal.
The useful d.c. component is related to the average luminance of the picture. It may or may not be contained in the signal and need not be transmitted nor delivered at the output. It is not contained in the signal if emphasis networks are used.
An unwanted d.c. component may be present in the signal due, for example, to direct- coupled baseband amplifiers. Limits for this component need to be specified for the terminated and unterminated conditions.
For an ideal system, linear waveform distortion is independent of the level of the applicd signal within the normal range of operating levels. The form of the video signal and the effects on a displayed picture are such that the resulting impairments may be classified within four different time scales, which are comparable with the duration of many fields, one field, one line and one picture element, respectively. In considering each of these time-scales, impairments appropriate to the other three are excluded by the measuring method.
Linear waveform distortion arises from a number of different causes and to fully evaluate its effect in a system, a number of controlled tests are necessary.IEC-60510-3-3-1988

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