Hello,
I also want to come with few comments on the antenna height.
We (me + OK1RF) do have here two antennas for 20m, one in 24m and one on
different tower in 52m above the ground. As a rule of a thumb while working
east coast the lower antenna is significantly better than the higher one, the
difference is ranging from practicaly zero to well over 6 S units !! It is very
very propagation sensitive - avarege difference is about 2 S units in favor of
the low antenna. Situation when the high antenna is better was already observed
but is very rare and from the contesting point of view negligible.
Exactly opposite is the situation with west coast, there is the high antenna
usualy about 1-2S units better but there were observed situations when W6,W7
station was 59+10 on the high antenna and not audible on the "low" one. Also
the other was observed, the signals on the low antenna can be 2S units better
compared to the high ant and it is more often the the opposite on the east
coast.
All this is very very time + propagation dependent. You might observe rapid
changes during 10 minutes periods while listening to same station as the skip
in the ionosphere changes and/or drifts.
The conclusion which most probably evrybody will agree with is:
the more various antennas you have the bigger chance you"ll going to
work them
73 !
Jiri - OK1RI
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