摘要
从实用的角度出发,概述了电化教学闭路电视系统前端部分的设计思路,从频道设置、线路设计、电平计算、设备选型等方面具体阐述了电化教学闭路电视系统前端设计的基本概念和方法。该系统方案可作为一般学校设计电化教学闭路电视系统时的参考。
This paper,by combining theory and practice,deals with the design of the front part of the dosed circuit TV system in the audio-visual teaching and some relative points for attention.In designing the system of dosed circuit most of schools and universities might take this paper for reference.
关键词
电化教学
闭路电视系统
线路设计
电平计算
频道设置
载噪比
channel fix
the design of the front circuit
the calculation of electric average
the CNR calculation of noise rate