Another twist to this format is that in most cases the
In the digital world – SDI, DV, MPEG and other formats, the synchronization signals either travel in a special digital sync channel or, in most cases, are embedded in the digital signal.
Due to the extensive use of sync related products, serious problems concerning sync signals may arise such as improper analog sync levels, damaged vertical sync, sync deterioration and improper polarity of the horizontal and vertical syncs.
1.2Video Sync Processors
Kramer Electronics has a full line of Video Sync Processors that can perform sync stabilization, restoration and conversion n the following categories:
Video Sync Generators: Generate standard video sync and black burst for studio genlock.
Video Sync Converters: Convert between the different sync formats - Composite, separate H & V syncs and Analog or TTL level. One machine in this category does sync to Green adding and separating.
Video Sync Restorers: Restore and
1.3Factors Affecting Quality of Results
There are many factors affecting the quality of results when signals are transmitted from a source to an acceptor as described in Table 1:
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| Table 1: Factors Affecting Quality of Results |
FACTOR | EFFECT | |
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|
Connection cables: |
| Low quality cables are susceptible to interference; they degrade signal quality |
|
| due to poor matching and cause elevated noise levels. They should therefore be |
|
| of the best quality. |
Sockets and connectors of |
| So often ignored, they should be of highest quality, since "Zero Ohm" connection |
the sources and acceptors: |
| resistance is the objective. Sockets and connectors also must match the required |
|
| impedance (75ohm in video). Cheap, low quality connectors tend to rust, thus |
|
| causing breaks in the signal path. |
Amplifying circuitry: |
| Must have quality performance when the desired end result is high linearity, low |
|
| distortion and low noise operation. |
|
|
|
Distance between sources |
| Plays a major role in the final result. For long distances between sources and |
and acceptors: |
| acceptors, special measures should be taken in order to avoid cable losses. These |
|
| include using higher quality cables or adding line amplifiers. |
|
|
|
Interference from |
| These can have an adverse effect on signal quality. Balanced audio lines are less |
neighboring electrical |
| prone to interference, but unbalanced audio should be installed far from any |
appliances: |
| mains power cables, electric motors, transmitters, etc. even when the cables are |
|
| shielded. |
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