Cypress CPA-3 operation manual Purity Application

Purity

Application

WHITE

BLACK

Purity Color White,

Blue, Red,

Magenta, Green,

Cyan, Yellow, Black

The red and green patterns are most frequently used for checking color purity. In a correctly adjusted receiver, each electron beam will strike only one set of color dots or stripes on the screen. If the red pattern is selected only this color should be visible; the presence of any other color is an indication that color purity needs adjustment.

The green pattern provides a purity check for three in-line tubes. In addition the pattern serves as a reference to locate any geometrical distortions in these picture tubes. In the in-line tubes, the guns are in a horizontal position and the green gun is located in the center.

Blue as well as the complementary colors are often used to check the color performance.

The Patterns (mainly RED) are used to ensure that there is no interference between the sound and chroma carrier.

In addition to the primary and complementary colors 100% white can be selected as well as black pattern with color burst to check.

Furthermore purity patterns are used for measuring unwanted amplitude and phase modulation of the subcarrier, AM and PM noise as it occurs with VCRs.

Black / White Line

Application

H/V B/W line

The vertical pattern serves for a quick check of color monitor’s horizontal bandwidth and phase behavior of a video transmission. Also, verify video am- plifier and color temperature.

The horizontal pattern serves for a quick check of color monitor’s vertical bandwidth and phase behavior of a video transmission. Also, verify video am- plifier and color temperature.

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