公开(公告)号：US3711738A

公开(公告)日：1973-01-16

申请号：US3711738D

申请日：1971-05-01

Applicant: RCA CORP

Inventor： FITZGERALD W ,  LEMMON R

IPC: H04N3/223 ,  H01J29/70

CPC classification number: H04N3/223

Abstract: Uncontrolled variations in the beam current drawn by the cathode-ray picture tube of a television receiver can cause such increases in the high voltage developed for its ultor electrode as will present problems of X-radiation. These uncontrolled variations can also result in a loading of the horizontal deflection circuits of the receiver and cause the reproduced image to change in width. The described circuit operates to limit such undesired effects, both in the presence of these changes in beam current and, also, in the presence of variations in line voltage. A transistor referenced against ground potential is employed to develop a control voltage for the screen grid of the horizontal output tube and to provide the primary amplification needed to compensatingly offset these changes. Pulses developed across a secondary winding of the horizontal output transformer are monitored to establish the conduction state of the transistor to provide the desired control.

Abstract translation: 由电视接收机的阴极射线显像管吸收的束电流的不受控制的变化会引起对其阳极电极产生的高电压的这种增加，这将引起X辐射的问题。 这些不受控制的变化也可能导致接收器的水平偏转电路的加载并且使得再现的图像的宽度变化。 所描述的电路操作以限制这种不期望的效应，无论是在射束电流的这些变化的存在下，还存在线电压的变化。 采用基于地电势的晶体管来开发用于水平输出管的屏栅的控制电压，并且提供补偿地抵消这些变化所需的初级放大。 监控水平输出变压器的次级绕组上产生的脉冲以建立晶体管的导通状态以提供所需的控制。