Hi gang,
thanks for nice and encouraging suggestions for my topband ambitions.
Regarding optimal antenna, many suggested Inverted L...
I did some modeling in AO6.5 today.
Inverted L with 65ft vertical aluminum 2inch o.d. portion, plus 70ft
horizontal copper wire, 30 radials, 300m away from salt water = Nice low
angle pattern, max gain cca 2.5dBi at 10 deg elevation.
Inverted V, same height, same soil, no radials = nice high angle pattern,
but 7.5dBi max gain, and still competitive to Inv.L at 10 deg elevation
angle...
If you are familiar with AO6.x by K6STI, I used maximum number of pulses
(211), automatic segmentation on. After adding more and more radials, Inv-L
came with 5dBi gain at 10deg angle. That makes me think that just a few
radials is wasting time. Or modeling in AO is wasting time, hi.
The recent reports on topband condx are showing the real fun when the angles
are high. So, why bother with lowering the takeoff angle, just wait for good
condx and tune an inverted V? Remember, I am no engineer, but an architect,
and sometimes the aestethic gets important. Inverted V is so elegant :-).
Besides, reading about the problems with BC stations garbage, I realise that
I should start with receiving antenna first, trying to locate possible local
noise sources, hire a lawyer and hope that broadcasters would take me
serious... hmm, hmm.
Anyway, look for YT6O in the upcoming 160m openings.
73 Kele YT6O, YU1AO/6, N2KAB
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