Samsung CS29Z30SPBXBWT, Service Manual

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Circuit Description
Samsung Electronics 13-3
13-2 Partial Block Description
13-2-1 Vertical & N/S Correction Circuit
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Understanding of N/S Circuit and Operation Principle.
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What is a N/S correction circuit?
- If the bias angle of a picture widens, the distance from the center of a picture to each corner becomes farther as it moves to
periphery. This causes the picture being distorted (Picture Lowering) vertically in a shape of a spool because of the strong
bias at four corners which are the farthest from the center.
Correction effect to the amount of a correction signal can be made by crossing Parabolic current of a vertical period over the
vertical bias current and applying it.
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N/S Circuit Constitution and Operation Principle.
- Consists of L304, C305, C439, R312. Symmetrize the up and down amplitude using the saturable reactor of L304 and adjust
N/S Gain by controlling the capacity value of C305 and C439
If the correction vector is excessive, one can slightly reduce the resistance of R312