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Analog video

Analog (NTSC composit) video is presently being phased out. Analog has been with us since the beginning of television: about 1941. Analog has not changed much sence it's inception, except a small change in 1953 for color. NTSC has been, until recently, used in everything. It is used in cameras, tv sets, and broadcasting equipment. No one can deny analog was the only game in town for over fifty years, and has served us well.
I have worked in analog for over 35 years: Personally bound and licenced by the FCC.

VIR reference data is on line 19
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REFERENCE WHITE
Reference white sets the reference that the active video lines should match.

LUMINANCE
The average (center) "brightness" of the picture can be automated according to line 19 luminance.

BURST
Burst is on every active video line.
And will set the phase color, (or hue), for that line.

CHROMA
Defines the color "richness" of all active video lines that follow for one or two fields.
The engineer must calibrate and guarantee that full field chroma on active video lines do, indeed, match the reference on line 19.

SYNC
Sync is a timing signal and is not seen by the viewer. Sync is a huge drawback of NTSC. It constitutes the lagest power usage of the signal and is for something not seen.




WHITE REFERENCE
For "dots" to be visible, there must be lines that contain reference whites in the vertical interval area.

WHITES FULL FIELD
Active whites must not exceed 100 IRE units.

HSYNC HORIZONTAL FULL FIELD SYNC
63.5 uS between HSync

VSYNC of VERTICAL BLANKING
6 lines of Equalizing pulses followed by the 6 lines of Vertical Interval Serration, And user option lines make a total of 21 lines.
All 21 lines form Vertical Blanking.




SYNC
Sync is 40 units, extending from 0 IRE to -40 IRE.
Lines 1–9 are used for the vertical-sync and equalizing pulses

VECTOR SCOPE

There are many types of test signals used at broadcast facilitys. It is color "BARS" that are displayed on any vectorscope.

One sees two chroma reference bursts on line 18. (Unfortunate, but reality) One burst is on field one of line18, the other burst is on field two of line18. Bars ore on field one, and there is no way to know this from just the picture. A vectorscope can display full field bars (all lines) or just one line of bars.

Red is high in amplitude, but phase is ok.
Magenta is high and -2degrees (towards reddish)
Blue is dead on