Richard Clark wrote:
On Tue, 21 Jun 2005 22:25:32 +0100, Ian White GM3SEK
wrote:


When
there has been a reflection, the samples have opposite polarity and
cancel. When there has been no reflection the samples from that
direction of travel are in-phase and the sample total is double the
contribution of either sample.

Er, yes, pretty much...

Hi Ian,

To this point there is no controversy, no dispute. Why you should
hedge your assent remains elliptical

I was giving Richard H the chance to notice that wasn't quite correct,
that's all.


and probably lies with what you
have to say following.

That's because it doesn't actually measure watts. It has been calibrated
in watts under certain specific test conditions, using a different kind
of wattmeter that actually does measure watts.

All power displays derive from some operations of an implied
mathematical operation and all power displays employ scaling. They
may, each, perform their job through different methods, but all such
methods are still abstractions that require transformation to a common
expression of power. There is nothing distinctive between these
methods (the only separable characteristic) that negates the others
results.

You are going to have to be more explicit about why the Bird's
expression of Power does not yield that characteristic.

Simply because the theory that converts the Bird's raw readings
(actually rectified RF voltage) into "Watts" on the printed scale is the
very topic that is under discussion.

That means the Bird's readings of "watts" cannot be called as evidence
in the debate. Any argument based on doing so is doomed to be circular.
It *may* still be correct, but that cannot be proved through a circular
argument - you have to find some other way.


--
73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek