Complete signal generator set with USB cable, designed to work with HDTVs, LCD monitors, and CRT projectors, providing a reliable tool for diagnosing display issues. Four resolution modes: easily switch between four common settings 640x480, 800x600, 1024x768, and 1280x Each mode is powered by a 9V battery or an external AC adapter for flexible use. User friendly operation: connect the generator to your display using the 15 pin connector and select your desired signal. The default color block diagram appears upon startup for immediate testing. Compact and lightweight design: dimensions 26 mm x 52 mm x 90 mm, making it easy to transport and store for quick diagnostics. Use scenarios Field technicians performing on site diagnostics across various display devices to identify issues quickly. Home users during setup or to verify signal compatibility between computer sources and displays. Educators or presenters testing projectors and monitors in classrooms or conference rooms for reliable signal output.