Update: 27 Dec 2017. The splitter design I originally used did not produce zero phase difference. Hence I have updated this page with another design.
I built this splitter based on a design from EMRFD (Experimental Methods in RF Design, Hayward, Campbell & Larkin), specifically the one from the 18 MHz transceiver shown in Fig. 11.14.
The schematic is below:
I used an FT50-43 toroid with 6 bifilar turns.
My built version can be seen in the picture below.
The picture below shows the outputs from ports 1 and 2. They are equal in amplitude and in phase which is perfect.
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