TRANSMITTER COMBINER HAVING COUPLED TUNED CIRCUITS

• US 3,735,289 A
• Filed: 11/26/1971
• Issued: 05/22/1973
• Est. Priority Date: 11/26/1971
• Status: Expired due to Term

• Current Assignee: Warren B. Bruene
• Original Assignee: Warren B. Bruene
• Inventors: Bruene, Warren B.
• Primary Examiner(s): Gensler, Paul L.
• Application Number:
  US05/202,330
• Time in Patent Office: 543 Days
• Field of Search: 333/4,5,6,8,77,78,82B 343/858,889,865 334/45,46 329/142 325/171
• US Class Current: 333/5
• CPC Class Codes: H01P 1/2133 using coaxial filters H01P1/2131, H01P1/2136 take precedence
• CPC Class Codes: H01P 5/16 Conjugate devices, i.e. devices having at least one port decoupled from one other port

Abstract

A hybrid coupler for coupling a plurality of transmitters to a single antenna. Inductive coupling through use of variable length transmission line stubs affords tuning over a wide transmission frequency range.

Claims

1. Means for combining the outputs from a plurality of radio transmitters for broadcast from a single antenna comprising at least first and second tuned circuits each including a variable capacitive element and a variable inductive element connected in parallel, first input means for applying a first transmitter output to said first tuned circuit, second input means for applying a second transmitter output to said second tuned circuit, dummy load means connected between said two input means, a third tuned circuit including a variable capacitive element and a variable inductive element connected in parallel, cavity means, said inductive elements comprising coaxial transmission line stubs within said cavity means, movable shorting plane means for varying the electrical lengths of said stubs whereby said inductive elements of said first and second tuned circuits are tunably magnetically coupled with said inductive element of third tuned circuit, and output means for applying an induced voltage in said third tuned circuit to antenna means.

2. Means as defined by claim 1 wherein said inputs and said output are unbalanced and said dummy load means comprise resistive means in said transmission line stubs in said first and second tuned circuits, and including conductive means interconnecting the center conductors of said stubs in said first and second tuned circuits.

3. Means as defined by claim 1 wherein said inputs and said output are balanced and said dummy load means comprise resistive means connected to first and second transmission lines, said first and second transmission lines extending within said transmission line stubs in said first and second tuned circuits, respectively, and means within said cavity interconnecting the center conductors of said first and second transmission lines.

4. Means as defined by claim 1 wherein said inputs are unbalanced and said output is balanced and further including balun means within said cavity.