公开(公告)号：US3904819A

公开(公告)日：1975-09-09

申请号：US44070374

申请日：1974-02-08

申请人： COLOURVISION ASSOCIATES

发明人： SWORD GEOFFREY ,  LAWRENCE JOHN LESLIE ,  RAGGETT STEPHEN RICHARD ,  BLAKEMORE BERNARD

IPC分类号： H04N5/257 ,  H04N9/11 ,  H04N5/44

CPC分类号： H04N5/257 ,  H04N9/11

摘要： High voltage supply circuits for television apparatus. The current in a primary circuit of a transformer is determined by a transistor the impedance of which is controlled by negative feedback from a high voltage output coupled to the secondary circuit of the transformer. Current pulses in the primary are produced by switching another transistor in the primary circuit at television line frequency. The circuit can be employed to supply a dynode resistor chain of a photomultiplier in a flying spot colour television transmitter, the luminance signal being averaged by a long time constant integrating circuit and summed with the negative feedback to provide a further feedback control compensating for variation in the average density of film being scanned.

摘要翻译： 电视机高压电源电路。 变压器初级电路中的电流由晶体管确定，晶体管的阻抗由耦合到变压器次级电路的高电压输出的负反馈控制。 通过在电视线频率处切换初级电路中的另一晶体管来产生初级电流中的电流脉冲。 该电路可用于在飞点彩色电视发射机中提供光电倍增管的倍增电阻链，亮度信号被长时间常数积分电路平均，并与负反馈相加，以提供进一步的反馈控制， 正在扫描的胶片的平均密度。