[Amps] hit a wall on bi-directional couplers

[Dan Sawyer]

All,

I have hit a wall on bidirectional couplers for HF. I have breadboarded 
the bi-directional portion of the following attached bi-directional 
coupler circuit. It appears in principal to be the same as the circuit 
in the arrl antenna handbook.

http://www.ramseyelectronics.com/downloads/manuals/PM10DC.pdf

I did not terminate either coupler output, I simply sampled them for 
voltage with a high impedance scope probe.  The net net is there is no 
difference between the outputs and they are both high, about 3 db down 
from the input. I did not use a 'binocular' transformer but used two 
tube types in the same configuration.  I was very careful to wind the 
transformers exactly as described in the text.  The feed through is a 
piece of copper wire centered in the transformer by an insulator. The RF 
output is terminated in 50 Ohms.

I would appreciate pointers, advice, links to primers, or links to 
alternatives.  Thanks - Dan kb0qil