[TowerTalk] SWR is what SWR meter measures

[Tom Rauch]

Hi Ian,

Nice to see you again!

> 22. Don't even THINK about "net" power being the
difference between
> "forward power" and "reflected power".  You don't need to
go there... so
> don't.

It works perfectly, or as perfectly as I can measure, on my
meters.

> The problem with using those real-life measurements to
calculate the
> ratio of "forward power to reflected power" is that it
suddenly requires
> us to know things about the transmitter! We're now saying
that we need
> to know the type of transmitter, how it is tuned, driven
and loaded, etc
> etc. But that flatly contradicts what we said in the
previous paragraph
> - namely that we can know everything about the
transmission line and
> antenna, without needing to know *anything* about the
transmitter.

No we don't. It works with any source Ian.

When you use a directional coupler power meter to measure
forward power and when the load is not matched to the meter
the forward and reflected readings increase. When reflected
power is subtracted from forward power we are left with the
power delivered to the feedline.

It works just fine in every case I have seen. It never is
affected by the transmitter.

73 Tom