Topband: Low Dipoles

[m.r.c.]

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 at alum.mit.edu>
To: "topband" <topband at 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
> _________________
> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector