Hi John
What is the orientation of you low dipole? I assume similar to XZ0A it is
broadside N-S. In 2010 the SSW SSE propagation that I am calling TELP
started with solid copy for 2 weeks in October of XU7ACY around 11:15z and
at 2 weeks per month until March. 2011 was even better and Dec 29 and 30th
were the best days I ever experienced LP. January 2012 this propagation just
stopped from the best day to zero. Nada!!! During 2013 and 2014 LP on 160m
was very rare. 2014 we had some good days with HS0 and DU7 per month., not
even close to what happened 2010 , 2011. Also very few days opening near SS.
I think your observation is the same as my , the dipole advantage became
non-existent 2013 - 2014 because there was no propagation SSE SSW or TELP. I
used to monitor a BC on 3915 from 9V1 to check for SSE SSW propagation but
the station went QRT last March and I don't have another signal to check
propagation from South Asia anymore so we depend on activity to know is the
band is open and activity has been very low.
I hope the SSW SSE propagation mode will be back next season, or maybe it
will start like it stopped with a huge opening.
Regards
JCarlos
N4IS
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of John
Kaufmann
Sent: Thursday, December 18, 2014 8:43 PM
To: 'Top Band Contesting'
Subject: Re: Topband: Non-resonant receive antennas
A few years ago, I put up a low, non-resonant dipole, about 150 feet long
and 10 feet high for use as an auxiliary receiving antenna on 160. My main
receiving antenna was and still is an array of short verticals. What I
found at my W1 location after I installed the dipole is similar to what N5IA
described at XZ0A.
If the band was open before my local sunrise (not always the case!), the
verticals would always outperform the dipole by a large amount. However, as
soon as we hit sunrise, the dipole would suddenly start equaling and then
outperforming the verticals. The transition would take place in a matter of
a few short minutes. Past sunrise, DX signals would drop into the noise on
the verticals but would continue to hang in on the dipole. The dipole would
sometimes extend the opening for me by 5 to 15 minutes, allowing me to make
some contacts (mainly JA and VK, if the band was open in those directions)
that would not have been possible with the vertical array. Sometimes the DX
would be virtually inaudible on the verticals but Q5, although not strong,
on the dipole.
What is rather interesting, however, is that in the winter seasons of
2012-2013 and 2013-2014, this dipole advantage became non-existent. The
dipole was never even close to the verticals, either before or after
sunrise. It caused me to go outside a number of times to see if the dipole
had fallen down, but that was never the case. Evidently the propagation
mechanisms at work around sunrise have changed from a few years ago, at
least at my QTH. So far in the 2014-2015 season, the dipole has still not
provided any receiving advantage around sunrise.
I generally don't operate much around local sunset, but I have never seen
any dipole advantage at sunset.
73, John W1FV
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