In message , Reg Edwards
writes
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.
---
Reg ;o)



Reg, I thought that a DC was essentially any device which sampled some
of the RF signal travelling in one direction, and (if perfect) none of
the signal travelling in the other. Over the past 40 years, I have had
lots of dealings with them. I've even designed some which were bought in
their thousands (if not millions). Some of them seemed to work from
below 5MHz to over 870MHz (well, I THOUGHT they did, and so did the
people who bought them).

Where did I go wrong?

On the positive side, I never went as far as to claim that they would
measure SWR.

Ian.
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