W8JI@aol.com wrote:
> 4.) When you measure power, be sure to subtract the reflected power
> from forward power to get true forward power. Use a low power slug to >
> measure reflected power, keeping the meter near full scale for both
> readings. Otherwise, you have to add in the error in reflected power, >
> since it directly affects the true forward power and SWR readings
The above is absolute nonsense. Reference "Reflections", Chapter 4,
page 4-10
> 5.) The best way to measure power is to build a very low loss tuner low
> operating Q tuner using high quality components (efficiency above 98%) > and
> use that matching network to insure the load Zo is always 50 ohms. > This
> eliminates reflected power meter errors and the accumulated
> errors of reflected power and forwrad power subtraction.
Use the same reference. A tuner maintains a constant Zo ONLY between the
signal generater and the tuner. It has absolutely nothing to do with
VSWR on the transmission line, unless of course, the tuner connects
directly to a antenna. And if such were the case, VSWR does not, by
definition exist.
73
Ed
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