N0FP writes:
>>The last few nights, the reports through polar paths are consistantly
stronger than what I am hearing on my end. My noise floor is near S0 when
the local power lines are not arching over. Path to Panama were consistant
with the reciprocity principle. Polar paths were more "one way." Finland,
Sweden, and Germany all reported better signals than what I am hearing with
similar power on both ends.
Is it propagation or some anomoly with my new antennas?
<<
W8JI writes:
>>I've been wondering how to test path direction differences for years.
The only way I can think of testing path direction differences is to
have systems with calibrated signal level voltage meters and antennas
with identical properly focused patterns. The systems would also have
to have known power and antenna efficiencies at each end of the path,
and we would have to do a chart recording. <<
K3BU notes:
Contrary to W8JI assertions that propagation media is "linear" and
reciprocal, there are situations when this is not so.
One proof without chart recorders is that we often have a situation when we
hear the station well, but cannot get through (keeps CQing in your face -
guhor). Later on situation can reverse or conditions allow QSO with different
signal levels. (unbelievers can insert "arguments" like local noise, etc.)
Just don't bet on fact that if you hear station S7, he has to hear you S7
when you have identical power and antennas. It is not much anomaly, it
happens quite often. Just wait "your time" and propagation to get "right" for
both of you or maybe not. (I recall calling XZ1A for hours without getting
peep or a point in the contest.) Refraction and ducting can 'splain that
better than "mirrors" theory.
Yuri, K3BU, VE1BY, VE3BMV
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