At XZ0A we would not have made about 50% of our NA contacts if we had not installed a low receiving
dipole. It was the ONLY antenna that could hear NA stations for the hours at sunset and just after.
These were clearly skew paths as the NA stations all had to use antennas aimed to the SW in order to hear
us. This during the solar maxima. We did not transmit on the low dipole because it was too low, several
hundred feet away, not fed with transmit grade cable, and portions were supported by the all encompassing
wet brush. It would have been a nice experiment if we had been able to transmit on that antenna.
Robin
WA6CDR
XZ0A-XZ1N-VP6DX
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: "topband" <topband@contesting.com>
Sent: Monday, December 14, 2020 05:31
Subject: Re: Topband: Low Dipoles
W3LPL wrote:
"I've never found them to be more effective receiving antennas than Beverages
or arrays of short verticals at sunset or at any time during the night"
I have a inverted-V with apex at 100' and ends at 30' that I specifically
put up for high angle conditions. I also have a quasi-4SQ Tx antenna about
300' away. The Eznec plot below shows the breakeven TOA is around 45
degrees. I usually see +10 dB in favor of the 4SQ which you can see on the
plot happens at TOAs below 15 degrees.
https://photos.google.com/photo/AF1QipM_OgfeUmNPr7fPJL2YApvxE5HaQbajJDfYlD-M
Most (>99%) of the time what Frank says is true. However there are rare
occasions when the inv-V is stronger than the 4SQ indicating high angles.
Normally I receive on Beverages and TX on the 4SQ but the tipoff to check
for high angles is when Beverages lose directivity. When this happens it
indicates high angles, so I then switch to both TX/RX on the inv-V. For me
this most often occurs just after sunset and only lasts 30 minutes or so.
However in contests I've had significant runs of deep z16 and even deeper
stations which have significantly added to my points and mult totals.
Sunrise also shows peaks but not as pronounced as sunset. High angles can
also occur during significant solar events but this is more rare than at
sunset/sunrise.
"You can never have too many antennas!"
73, Bill W4ZV
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