On Tue, 07 Oct 2003 13:54:34 -0500, Cecil Moore
wrote:

Richard Clark wrote:

wrote:
OK, here's an interesting data point. I adjusted my IC-756PRO for 5W
output on 7.2 MHz using the following circuit.

7.2MHz 5W source---(+j442)---(-j442)---50 ohm dummy load

SWR meter at the dummy load read 5W forward with an SWR of 1:1

Then I installed the SWR meter between the coil and the cap. With 5W
supplied by the source, the forward power read 150 watts. Indicated
SWR was 3:1

Hi Cecil, And so?

And so it seems to support your variable SWR observations.

Hi Cecil,

With 5W supplied you read 150W forward?

Well that aside, it is not very remarkable to see 1:1 into a dummy
load. It is also not very remarkable to see 3:1 into a complex load.
You do not state you have any transmission line between the two
reactances until you dropped in the SWR meter, that isn't particularly
meaningful either. So, in the end, you demonstrate nothing of my
examples that have always been premised with a transmission line being
integral to the concept.

The short of it: I have always described this as a problem involving
two resistors and a hank of line. The long of it: You have merely
demonstrated your own invention of two conjugated reactances and one
resistor - not the same thing at all, not even conceptually.

Now, if you added a 1foot length between the two reactances, and then
replaced that with a two foot length, and then replaced that with a
three foot length, and then replaced that with a four foot length....
out to at least half a wave of electrical length. And all the while
taking forward and reverse power readings (or SWR, take your choice)
and specified the frequency THEN and ONLY THEN would you be able to
make a first pass comparison.

To take an observation from Metrology: one measurement tells you
nothing of any accuracy, two measurements only confuse, three begins
to reveal a true measure, more improves matters. Your two readings
say nothing to the matter (Mismatch Uncertainty) and actually confirm
expectations that lie outside of my examples.

73's
Richard Clark, KB7QHC