Multi-layer card attenuator for microwave frequencies

Claim 2

A MICROWAVE ATTENUATOR COMPRISING (A) A COAXIAL CONNECTOR HAVING AN OUTER CONDUCTIVE MEMBER AND AN INNER CONDUCTIVE MEMBER COAXIALLY SPACED AND INSULATED THEREFROM, (B:) A THIN LAYER OF RESISTIVE MATERIAL UNIFORMLY DISTRIBUTED OVER AN AREA DEFINING A SURFACE, (C) SAID SURFACE AREA COMPRISING TWO SUB-AREAS OF DIFFERENT UNIT RESISTIVEITY, THE SUB-AREA OF LOWER UNIT RESISTIVITY BEING IN GOOD CONDUCTIVE CONTACT WITH SAID INNER CONDUCTIVE MEMBER AND THE SUB-AREA OF HIGHER RESISTIVIETY BEING IN GOOD CONDUCTIVE CONTACT WITH SAID OUTER CONDUCTIVE MEMBER.

Claim 3

A MICROWAVE ATTENUATOR COMPRISING (A) AN INSULATING MEMBER HAVING AT LEAST ONE PLANE SURFACE, (B) A THIN LAYER OF RESISTIVE MATERIAL ON SAID SURFACE (C) A COAXIAL CONNECTOR HAVING AN OUTER CONDUCTIVE GROUNDED MEMBER AND AN INNER CONDUCTIVE CURRENT MEMBER COAXIALLY SPACED AND INSULATED FROM SAID OUTER MEMBER, (D) AN OUTER HOLLOW TUBULAR CONDUCTOR ELECTRICALLY CONNECTED AT ONE END TO SAID OUTER CONDUCTIVE MEMBER, SAID INSULATING MEMBER LYING WITHIN SAID HOLLOW MEMBER WITH SAID RESISTIVE MATERIAL IN CONTACT WITH THE TUBULAR CONDUCTOR ALONG A LINE OF CONTACT PARALLEL TO THE CENTRAL AXIS OF THE TUBULAR MEMBER BUT SPACED THEREFROM, (E) SAID INNER CONDUCTIVE BEING IN CONTACT WITH SAID RESISTIVE MATERIAL AT A LOCUS SPACED FROM SAID LINE OF CONTACT WHEREBY CURRENT CAN FLOW THROUGH SAID ATTENUATOR BETWEEN THE INNER CONDUCTIVE MEMBER AND THE OUTER CONDUCTIVE MEMBER, (F) THE INNER SURFACE OF THE TUBULAR MEMBER BEING SO SHAPED IN CROSS-SECTION THAT THE DISTANCE FROM THE CENTRAL AXIS TO SAID LINE OF CONTACT IS GREATER THAN THE DISTANCE FROM THE CENTRAL AXIS TO ANY OTHER AXIS LINE ON SAID INNER SURFACE, WHEREBY THE CUT-OFF FREQUENCY IS HIGHER THAN FOR A CYLINDRICAL HOLLOW MEMBER ENCLOSING A RESISTIVE MEMBER OF THE SAME DIMENSIONS.

Claim 4

A MICROWAVE ATTENUATOR COMPRISING (A) AN INSULATING MEMBER HAVING AT LEAST ONE PLANE SURFACE, (B) A THIN LAYER OF RESISTIVE MATERIAL ON SAID SURFACE (C) A COAXIAL CONNECTOR HAVING AN OUTER CONDUCTIVE GROUNDED MEMBER AND AN INNER CONDUCTIVE CURRENT MEMBER COAXIALLY SPACED AND INSULATED FROM SAID OUTER MEMBER, (D) AN OUTER HOLLOW TUBULAR CONDUCTOR ELECTRICALLY CONNECTED AT ONE END TO SAID OUTER CONDUCTIVE MEMBER, SAID INSULATING MEMBER LYING WITHIN SAID HOLLOW MEMBER WITH SAID RESISTIVE MATERIAL IN CONTACT WITH THE TUBULAR CONDUCTOR ALONG A LINE OF CONTACT PARALLEL TO THE CENTRAL AXIS OF THE TUBULAR MEMBER BUT SPACED THEREFROM, (E) SAID INNER CONDUCTIVE BEING IN CONTACT WITH SAID RESISTIVE MATERIAL AT A LOCUS SPACED FROM SAID LINE OF CONTACT WHEREBY CURRENT CAN FLOW THROUGH SAID ATTENUATOR BETWEEN THE INNER CONDUCTIVE MEMBER AND THE OUTER CONDUCTIVE MEMBER, (F) THE INNER SURFACE OF THE TUBULAR MEMBER BEING SO SHAPED IN CROSS-SECTION THAT THE DISTANCE FROM THE CENTRAL AXIS TO SAID LINE OF CONTACT IS GREATER THAN THE DISTANCE FROM THE CENTRAL AXIS TO ANY OTHER AXIS LINE ON SAID INNER SURFACE, WHEREBY THE CUT-OFF FREQUENCY IS HIGHER THAN FOR A CYLINDRICAL HOLLOW MEMBER ENCLOSING A RESISTIVE MEMBER OF THE SAME DIMENSIONS.