Owen:

Right of you to be cautious of that wise and crafty old brit.

Not only has he survived in this den of treacherous and particularly
vicious hams--he has THRIVED--this is quite suspicious in itself!

However, most often you will find there is true wisdom in his words
and programs... and it is of a highly practical nature. He is a
welcomed resource here...

John

"Owen" wrote in message
...
On Wed, 6 Jul 2005 23:48:53 +0000 (UTC), "Reg Edwards"
wrote:

Owen,

Your formula is too short to be anything but an approximation. It
may
be a very good approximation. On the other hand it may contain
exactly the same errors as whatever you may have checked it against.

The exact formula is exceedingly involved and occupies about half a
dozen lines of source code in new program SWRARGUE which by
coincidence I have just placed in my website.

I have calculated the loss using P=Real(V*I*) at the two points, and
it is long winded. Michaels approach produces the same result, and
the
coding is more elegant, probably faster to calculate. He is a SK, so
I
can't ask him, but in the hope that it is well known, someone might
know of the derivation.


You can check your formula against my program. Let us know how you
get
on.

Your calculator does not allow complex Zo does it? Doesn't that mean
it assumes a distortionless line. I am calculating loss in the
general
case.

Thanks...

Owen

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