HiDef,
'Infinite' radiation resistance, in a dummy load? No. A dummy load exhibits a constant 'radiation resistance' at all (almost) frequencies, and it isn't infinite by any means. Remember that 'radiation resistance' is like the 'resistance' in impedance.
"Given a good match means whatever antenna under test is working to it's capability." I have to disagree with that, it depends on how you are meaning "Good Match", and how you do the measuring of that 'match'. If using an SWR meter, the statement is NOT true in all cases. There are many 'R +/- J' that will appear to be 'R50 +/- J0', and be far from it. ('J' = 'X' in the case of MFJ analyzers.)
Moving an antenna can change it's receiving/transmitting characteristics. Yes, it certainly can. But these test figures are all relative, not absolute. Meaning that considering that all of these tests are done in the same circumstances/conditions, they are 'relatively' true comparisons. Is you were to move one of those test antenna positions relative to others in the same test, those readings are no longer 'relatively' true. If the testing conditions are valid to start with, and if all tests are done in the same conditions, then those results are true for those conditions and comparisons. About like testing the hearablity of a particular sound, and then changing the strength of the signal fed to one speaker and not the other speaker being tested. (That's not the greatest analogy in the world, is it? Oh well.)
I do agree that those 3 and 6 dB results are not exactly believable. Can't say why, but they certainly are not what's normally seen, in a standardized testing situation.
- 'Doc
