Burst

(TV formats only)

 

Description:

The left side start with reference white (+100 IRE)

 

and black (+7.5 IRE) levels. This is followed by six

 

bursts of sine waves. Each burst is at a different

 

frequency forming vertical lines of various widths.

 

The frequencies, going from left to right, are 0.5, 1,

 

2, 3, 3.58 and 4.43 MHz.

Test:

Frequency Response

Method:

When viewed on a TV screen, the peak intensities

 

of the all of the bursts should match the white

 

reference level. The darkest portions between the

 

peaks should match the black reference level.

 

The image can also be used with a TV waveform

 

analyzer to check the frequency response of a video

 

system. One scan line of the image, as it would appear

 

on a waveform analyzer, is shown at the top of the

 

next page. High frequency roll-off (loss) would show

 

up as a decrease in the peak-to-peak swings on the

 

right side of the waveform. Low frequency roll-off

 

would show up as a decrease in the peak-to-peak

 

swings on the left side of the waveform.

 

Some waveform analyzers can be set to detect and

 

display the amplitude of the peaks. A typical

 

amplitude waveform for a good system is shown at

 

the bottom of the next page.

4-12

Chapter 4: Built-In Images

Model 801GC, 801GF & 801GX¥Rev. X1

Page 50
Image 50
Quantum Data 801GC, 801GF, 801GX manual Burst, TV formats only