To make an old CRT (Cathode Ray Tube) monitor display white light without using a computer, you can try the following steps:
Power on the monitor: Ensure that the CRT monitor is connected to a power source and turned on.
Adjust brightness and contrast: Locate the controls on the monitor to adjust the brightness and contrast settings. These are typically physical knobs or buttons on the monitor itself. Increase the brightness and contrast settings to their maximum levels. This will maximize the intensity of the light produced by the CRT.
Disconnect the video input: Unplug the video cable that connects the CRT monitor to the computer or other video source. This will result in the screen displaying a blank or black image.
Activate the built-in test mode (if available): Some CRT monitors have a built-in test mode that can display solid colors, including white. This mode is usually accessed by pressing a specific combination of buttons or through an on-screen menu. Refer to the monitor's user manual or search for the specific model's instructions on how to activate the test mode.
Use external devices: If the built-in test mode is not available, you can use external devices to generate a white light source. For example, you can connect a DVD player or a video camera with a white image or a white test pattern to the CRT monitor. This will project the white image onto the screen.
It's worth noting that CRT monitors are becoming increasingly obsolete, and their use has declined significantly with the advent of LCD and LED monitors. Additionally, CRT monitors can pose safety risks due to their high voltage components. Therefore, it's essential to exercise caution and refer to the specific manufacturer's instructions and safety guidelines when working with CRT monitors.