SYNCHRONIZATION
In CRT (Cathode Ray Tube) monitors, synchronization, also known as sync, refers to the process of coordinating the display's electron beam scanning with the incoming video signal. It ensures that the displayed image is properly aligned, stable, and free from distortions.
Sync signals are essential for CRT monitors to accurately reproduce the video content being sent to them. There are two main types of sync signals in CRT monitors: horizontal sync (H-sync) and vertical sync (V-sync).
Horizontal sync (H-sync) is responsible for synchronizing the horizontal scanning of the electron beam with the horizontal timing of the video signal. It ensures that each line of the video signal is correctly traced on the screen from left to right. H-sync signals are sent during the horizontal blanking interval, which is the period between the end of one line and the beginning of the next.
Vertical sync (V-sync) is responsible for synchronizing the vertical scanning of the electron beam with the vertical timing of the video signal. It ensures that each frame or field of the video signal is displayed in the correct sequence and at the appropriate rate. V-sync signals are sent during the vertical blanking interval, which is the period between the end of one frame or field and the beginning of the next.
By receiving and processing the sync signals, the CRT monitor precisely controls the movement of the electron beam, scanning the screen in a sequential and synchronized manner. This synchronization ensures that the video content is displayed without distortions such as tearing, rolling, or flickering.
To achieve proper sync, CRT monitors typically require the video source to provide compatible sync signals. These signals are often generated by the video graphics card or the video source device itself. The video signals are transmitted to the CRT monitor through connectors such as VGA (Video Graphics Array) or RGBHV (Red, Green, Blue, Horizontal Sync, Vertical Sync).
Sync is a critical aspect of CRT technology, as it ensures that the monitor accurately reproduces the video content and maintains a stable and well-aligned image. However, it's worth noting that with the transition to digital display technologies, such as LCD and LED screens, the concept of sync has become less prominent, as these displays utilize different methods for image rendering and synchronization.
Internal & external synch
In CRT (Cathode Ray Tube) technology, both internal and external sync refer to methods of synchronizing the electron beam scanning with the incoming video signal. They determine how the sync signals are generated and provided to the CRT monitor.
Internal sync refers to the synchronization signals that are generated internally within the CRT monitor itself. The monitor has built-in circuitry that generates the necessary sync signals based on its own timing and scanning mechanisms. This internal synchronization ensures that the electron beam scans the screen at the correct horizontal and vertical rates, aligning with the video signal.
External sync, on the other hand, refers to synchronization signals that are provided to the CRT monitor from an external video source or device. These external sync signals are generated by the video graphics card or the device sending the video signal. They carry the timing information necessary for the CRT monitor to synchronize its scanning with the video signal.
External sync signals are typically transmitted to the CRT monitor through dedicated connectors or cables, such as VGA (Video Graphics Array), RGBHV (Red, Green, Blue, Horizontal Sync, Vertical Sync), or composite video connectors. The external sync signals inform the CRT monitor about the timing of the video signal, including the horizontal and vertical sync intervals.
The choice between internal and external sync depends on the specific setup and requirements. In many cases, CRT monitors can support both options, allowing users to select the appropriate synchronization method based on their setup. Internal sync may be suitable when the CRT monitor is used as a standalone display without the need for external video sources. External sync is often preferred in scenarios where the CRT monitor is connected to external devices such as computers, video equipment, or gaming consoles.
Both internal and external sync methods are crucial for ensuring that the CRT monitor properly displays the video content with accurate timing, synchronization, and stability. They work together to align the electron beam scanning with the video signal, resulting in a coherent and well-defined image on the CRT screen.