Tarmo Tammaru wrote:

Cecil,
You saw my simulations of your example. I got an SWR of 66.3 for ZS=0 and
69.1 for ZS= j400. That is as close as I can resolve. I had thought that if
it was going to change, I would get an SWR of 1:1 for the conjugate matched
case. What I had neglected, and maybe you also, is the fact that when you
connect an SWR meter into the middle of a resonant series tuned circuit, the
current is 90 degrees out of phase with the voltage.

Well, almost 90 degrees. V*I*cos(theta) still has to equal the forward
power minus reflected power even at that point. A quick and dirty phasor
diagram seems to indicate that the SWR meter bridge circuitry would get
pretty screwed up at point 'x' in the following:

Source---w---(-j500)---x---(+j500)---y---50 ohm load
| |
+----------------braid---------------------+

The SWR meter would indicate close to 1:1 at points 'w' and 'y' but
would detect a forward and reflected power of approximately five times
the delivered power at point 'x', offscale on both needles, which is
what happened when I installed my SWR meter at that point.

The SWR bridge circuit phasor adds the two phasors. Even when they are
90 degrees out of phase, they add up to a large magnitude that gets
rectified and routed to the meter.

You may be correctly predicting the actual SWR but I doubt that you
are correctly predicting the response of the bridge circuitry in the
SWR meter.
--
73, Cecil, W5DXP