Synchronization

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Synchronization

• Circuits in a TV receiver must lock or
  synchronize with horizontal and vertical sync
  pulses from a source (staion camera) in order
  that the image on the CRT appears normal.
• Sync pulses are embedded in the composite video
  signal that is transmitted from the source.
• Each is amplified and separated in order to
  control their respective beam deflection circuits.

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Synchronization

• Process requires 1. Take off after video
  detector and video
  
• amplifier.
• 2. Sync stripping.
• 3. Noise gating
• 4. Integration
  (vertical separation)
• 5. Differentiation
  (horiz. separation)

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Synchronization contd.

• Sync stripping the video signal must be removed
  from the actual sync pulses in order to eliminate
  a random influence on horizontal and vertical
  sweep.
• Noise interference can masquerade or present
  itself as sync bursts.
• What are some of the sources of noise?
• Remedies Good antenna system
• Adaptive AGC
• Eliminate noise sources greater
  than the level of
• the video signal or noise
  cancellation.

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