Helmut Wabnig [email protected] --- -.dotat wrote:
Hello,
may I ask the gurus a question please.

What does a SWR meter actually display?

effective power
reactive power
apparent power


What does it display in the 1 : 1 case with optimal impedance matching
between transmitter, cable and antenna, I guess it's effective power,
but what does it display when matching is off, say, 1 : 5
or even worse, when the mismatch SWR is 1 : 10 or greater?
There are two pointers in the instrument, forward and reverse,
how do they add up? Why do forward power and reverse power both
increase in their values when the antenna is strongly mismatched,
but the displayed SWR remains the same?

Please elaborate a little on the answers for a beginner like me.
Thank you,
w.

SWR (Standing Wave Ratio) is a ratio so it is independant of absolute levels.

http://en.wikipedia.org/wiki/Standing_wave_ratio

As for what is diplayed, it depends on how the maker calibrated the
meter as most meters are acutally measuring a voltage across a given
resistance.

Usually it is in average power. One meter I have can be switched between
average and peak.

You have to look at the meter specs to know for any given meter.


--
Jim Pennino