STREAKING MEASUREMENT TEST CHART

                              REFLECTANCE

The TE175 is designed for measurement of the disturbance caused by the video

level in black areas to the right of or below the areas. Horizontal white lines are

positioned on a black background.

Definition of streaking measurements

Measurement of the disturbance caused by the video level in black areas to the

right of or below the areas.The disturbance is characterized by measuring the

duration of the delay before the video level corresponding to the normal video

level of the black is restored.

Measuring equipment

Video level meter; B/W monitor, oscilloscope, low-pass filter: 500 KHz

Measurement conditions

The chart illumination must be adjusted so that the white bars give a signal of

100% with average iris setting.

Gain: 0dB

Gamma corrector: OFF

Contour corrector: OFF

Knee corrector: OFF

Pedestal = 5% of nominal video level (= 35 mV)

Measurement procedure

The lines crossing the white lines are displayed on the oscilloscope and a

measurement is made at the R, G, B outputs. The measurement is repeated at

various taking account of the nature of the streaking observed on a control monitor.

In order to distinguish the effects of flare from the effects of streaking, a different

measurement may be made taking as reference the number of lines not crossing

the white surface which are affected only by flare.

Presentation of results

Worst peak deviation of black level in the streak compared with an adjacent black

outside the streak. Care must be taken to avoid the effect of flare from the white

bar. The result is given in percent of nominal amplitude 700 mV / 75 Ohms.