1.Which device in a fiber optic receiver converts optical energy into electrical signals?
1.光纤接收器中的哪种器件将光能转换为电信号？
2.To distribute a +3 dBmV coax signal to four televisions and one cable modem without amplification, which splitter configuration is most suitable?
2.要将 +3 dBmV 同轴电缆信号分配给四台电视和一台电缆调制解调器，且无需放大，哪种分配器配置最合适？
3.What termination resistance must be applied at the end of a coaxial video line to prevent reflections and ghosting?
3.为了防止反射和重影，必须在同轴视频线的末端施加多少欧姆的终端电阻？
4.Which device detects motion by analyzing changes in brightness within a defined screen area rather than using external sensors?
4.哪种设备通过分析定义屏幕区域内的亮度变化而不是使用外部传感器来检测运动？
5.Which function is NOT typically provided by digital multiplexing in CCTV systems?
5.以下哪项功能通常不是CCTV系统中数字多路复用提供的功能？
6.Which unit of measurement is commonly used to set iris or white levels in CCTV systems?
6.在CCTV系统中，通常使用哪种测量单位来设置光圈或白平衡？
7.Why do monochrome cameras often produce clearer images in low-light conditions?
7.为什么单色摄像机在弱光条件下通常能产生更清晰的图像？
8.Which statement correctly describes wide-angle lenses?
8.以下哪项描述正确地描述了广角镜头？
9.Which statement applies to most CCTV camera power installations?
9.以下哪项描述适用于大多数CCTV摄像机电源安装？
10.Why are telecom and CATV providers migrating toward fiber optic networks?
10.为什么电信和有线电视运营商正在向光纤网络迁移？
