Abstract A filter for a video amplifier of the type used to amplify a signal on a transmission line which also carries power for operating said amplifier comprises a tubular semiconductive ferrite member coated with barium titanate. An inner conductive layer is provided on the ferrite and an outer conductive layer on the barium titanate. A plurality of turns of insulated wire forms a winding which is connected to the inner conductive layer at a point which is also connected to the transmission line. The other end of the winding is connected to a power transformer for the amplifier. The video input of the amplifier is connected between the filter''s outer conductive coating and the power transformer. In another embodiment, the outer and inner conductive coatings are split and the filter is connected so that an effective shunting capacitance is connected across the power transformer. Alternatively, two filters of the type including tubular ferrite members, barium titanate and conductive coatings are used.
A filter device to be used in combination with an amplifier of the type used to amplify a signal on a transmission line which also carries power for operating said amplifier comprising: a composite tubular filter member including a tubular semiconductive ferrite element, a dielectric coating on said ferrite element, an inner conductive coating within said ferrite element, and an outer conductive coating over said dielectric coating; winding means of insulated wire wound upon said composite tubular filter member, said winding means being electrically connected to said inner conductive coating at one end of the winding means to which said transmission line is also connected; an amplifier video input means connected to said outer conductive coating; and a power transformer having its primary winding connected to the other end of said winding means and supplying power to said amplifier.
Claim 2
Dependent Claim
139 words
A filter device to be used in combination with an amplifier of the type used to amplify a signal on a transmission line which also carries power for operating said amplifier comprising: a composite tubular filter member including a tubular semiconductive ferrite element, a dielectric coating on said ferrite element, an inner conductive coating within said ferrite element, and an outer conductive coating over said dielectric coating; winding means of insulated wire wound upon said composite tubular filter member, said winding means being electrically connected to said inner conductive coating at one end of the winding means to which said transmission line is also connected; an amplifier video input means connected to said outer conductive coating; and a power transformer having its primary winding connected to the other end of said winding means and supplying power to said amplifier.
Claim 3
Dependent Claim
81 words
A filter device as recited in claim 1 wherein each of said inner and outer conductive coatings is separated by a gap into two conductive bands, said amplifier video input means being connected between the two outer conductive bands, said power transformer being connected between onE end of said winding means and one of said outer conductive bands to effectively shunt said power transformer with the capacitance between said one outer conductive band and said one end of said winding means.
Claim 4
Dependent Claim
136 words
A filter device as recited in claim 1 which further comprises: a second composite tubular filter member also including a tubular semiconductive ferrite element, a dielectric coating on the ferrite element, an inner conductive coating within the ferrite element, and an outer conductive coating over said dielectric coating; a second winding means wound on said second composite tubular member and electrically connected at one end thereof to the said other end of the first winding means, said second winding means being connected at its opposite end to said power transformer; and said amplifier video input means being connected between the two outer conductive coatings of the two composite filter members, with the effective capacitance between the inner and outer conductive coatings of said second composite tubular filter member forming a shunt capacitance across said power transformer.