What is the effect of VGA cable length on transmission quality?

VGA cable length has a great impact on transmission quality, mainly reflected in the following aspects:

• Signal attenuation: VGA cables transmit analog signals, and the signal strength gradually decreases as the line length increases. This can result in lower brightness, lower color saturation, and poorer contrast in the image. For example, when the VGA cable is too long,

the originally bright red may become dim, and the black part may also appear gray variegative, affecting the visual effect of the image.

• Image distortion: During long-distance transmission, the waveform of the signal may be distorted, resulting in distorted images such as gaping, blurring or blurred edges. For example, when text is displayed, the edges of the text may become blurred

 and difficult to read; When a graph is displayed, the outline of the graph may appear jagged or irregular.

• Increased interference: The longer the VGA cable, the more susceptible it is to external electromagnetic interference. The surrounding electrical equipment, power lines, etc., may produce electromagnetic waves, which will interfere with the signal in the VGA line, further reducing

the transmission quality. Interference may be manifested as horizontal stripes, snow spots or flickers on the image, and even affect the normal display of the image in serious cases.

In general, when the VGA line is within 15 meters, the transmission quality is relatively good, which can basically ensure the clarity and color reproduction of the image. When the length is more than 15 meters, the signal attenuation and interference will be

more obvious, need to use a signal amplifier or higher quality VGA cable to minimize the impact. If the VGA cable length is more than 30 meters, even if the signal amplifier is used, the image quality may be greatly affected, and it may be necessary to consider 

using other interfaces or transmission methods that are more suitable for long-distance transmission, such as HDMI fiber optic cables.