VK6HD wrote:
>At sunset, when I worked Jon, I was using the
>inverted vee, which was 2 S points up on the vertical. Thirty minutes after
>sunset...1201z the vertical and the inv.vee were the same on receive and 5
>minutes later the vertical was well ahead.
Hi Mike!
This parallels my experience in 1985 when I had an elevated
GP and dipole up 145' in Colorado. Both dipole supports were pulled
out 500' so it was fairly flat...i.e. not an inverted vee which has a
low angle pattern. I did tests daily to VK (VK3ZL, VK4YB, etc) each
summer morning with the following average results:
1 hour before sunrise: vertical + 1-2 S-units (5-10 db)
+/- 10 min around sunrise: both vertical and dipole equal
15-30 min after sunrise: dipole + 1-2 S-units
My Beverages generally were poor after sunrise and paralled the
vertical's performance (no surprise since both are low angle antennas).
The dipole was mostly radiating straight up since it was only ~1/4 wave
high. I even tried a reflector just above the ground to enhance the high
angle radiation (a la K3LR's cloud warmer antenna on 40) but could not
switch it in and out to tell if it made any real difference. The high
angle radiation from the dipole seemed insensitive to azimuth direction
(since most of the radiation was straight up). I recall working YB0ARA
(off the azimuthal side of the dipole) 20 minutes after sunrise when he
was completely inaudible on any Beverage or the vertical.
I did not observe the dipole was better at my sunset except on
rare occasions. It seems like the high angle mode was only at my sunrise
...unlike what you noticed.
73, Bill W4ZV
P.S. You were so strong on the 7th I thought you were a local station
until I heard your call!
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