Joel,
I'm giving some thought to how I would replicate your experiment to
satisfy my own curiosity, and I have a couple of questions about the
technique you used.
From your article I gather that when you changed the line conditions -
made it wet, dropped it onto the ground etc - the characteristic
impedance changed, and that you compensated by adjusting the tuner to
ensure that the line remained matched; however as far as I can see there
was no corresponding change in matching at the signal generator end.
That would mean the generator was "seeing" a different impedance for the
differing line conditions; consequently there would be a changing source
mismatch-loss and the generator would deliver different powers to the
line under the different line conditions.
I'm wondering:
1) When adjusting the tuner, how did you know when the line was matched?
2) How did you take account of the changing generator mis-match loss
when calculating the line loss?
Please don't think I'm trying to "challenge" your technique, I'm
genuinely trying to unravel some of the issues!
Thanks,
Steve G3TXQ
On 27/01/2012 13:52, Joel Hallas wrote:
Steve,
Thanks, yes I agree that it is important to be as correct as we can. Still,
I have confidence in our observations.
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