On Sun, 5 Sep 2004 12:18:09 +0000 (UTC), "Reg Edwards"
wrote:

|What's a directional coupler?
|What do they look like?
|Don't bother answering those questions.
|
|Why do the arguers, when caught in a tight corner, always escape to UHF for
|help from directional couplers?
|
|There are NO directional couplers at HF. They are as scarce as real swr
|meters. So they cannot be used in futile attempts to explain what really
|happens at HF.
|
|You're next move will be to drag in scattering-matrices.

Why not. I have used an HP3577 network analyzer with an S-parameter
test set that was specified to work over the frequency range of 100 Hz
to 200 Mhz.

I guess the guys at HP didn't realize that you can't do this.