Two input combiner having useful and dummy load outputs

Claim 1

A combiner network comprising an output port having a first terminal and a second terminal for supplying a load, a first input port having first and second terminals, a second input port having first and second terminals, the second terminals of the said input ports and the second terminal of the output port being directly connected together; a single transformer having a first winding and a second winding, the first winding being connected between the first terminal of the first input port and the first terminal of the output port, the second winding being connected between the first terminal of the output port and the first terminal of the second input port, said windings being oppositely wound with respect to current flow from the first and second input ports and having a respective turns ratio in inverse proportion to the respective rated input powers of the first and second input ports whereby under rated operating conditions the net flux attributable to current flow through said windings is substantially zero; dissipative impedance means having an impedance selected to balance rated load impedance and connected in a series loop with a third winding of said transformer, said third winding being mutually transformer-coupled with said first and second windings whereby, in response to non-zero net flux in said windings caused by flux imbalance between said windings, said dissipative impedance means is operative to dissipate a portion of the power supplied by said input ports so as to maintain an impedance balance between said input ports.