In a message dated 2/4/04 8:30:21 AM Eastern Standard Time,
>>The array of bewildering echoes, different beam headings that are DIFFERENT
based on the difference is height and other weird propagation effects sure
make a 4 stack a really fun antenna to play with. Unfortunately MOST of the
fun and games can be seen only at the top of the cycle at my qth. I look
forward to 2009 when it will be lots of fun again!<<
High sunspot years present higher, thicker atmosphere/ionosphere and variety
of angles for different distances. When we get to low sunspots, layers are
thiner, lower then the low angle antennas take over.
I have seen dramatic demonstration of huge difference in signals on 10m from
OK1RI and OK2RZ. RI was running fixed 4 stack, RZ three different systems, but
smaller. At the beginning of the opening RI was S9 and over, while RZ just in
the mud, breaking over the noise. In the middle of the opening RI was S7,
while RZ was 20 or more over 9.
RZ tried to phase two or three systems for max bang with me, but due to the
QSB it was impossible, he had to do it by using signal monitor locally in the
direction of NA and he succeded.
Then there is the "non-reciprocity phenomenon". When I was operating with my
stacked Quad-Yagi Razors I discovered that there was about 70% of the time
disagreement between which configuration was best on transmit vs. receive. I
would do quick check in the contest with station in the hot spot of running
combination was better on TX and then use that on TX and keep switching RX
combination depending on which was better on RX.
Yuri, VE3BMV, K3BU.us
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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