JPS6042649B

PURPOSE:To enlarge the attenuation of longitudinal voltage amplitude without scaling up the input circuit of a smoothing amplifier by connecting capacitors between the middle point between a supply-current extraction circuit and pre-equalizer, and a reference-potential connection point inside of the amplifier. CONSTITUTION:Capacitors C6 and C7 are connected to the middle point of the supply-current extraction circuit formed of resistances R1 and R2 and the middle point between resistances R5 and R6 of the pre-equalizer composed of resistances R3 to R6 and capacitors C1 and C2, and the connection point between capacitors C6 and C7 is connected to connection point 3 at the reference potetial inside of smoothing amplifr 5. Then, capacities of capacitors C6 and C7 are reduced and the attenuation of longitudinal amplitude is enlared without scaling up the circuit, thereby preventing the overload of amplifier 5.