----- Original Message -----
From: Mike Waters W0BTU
> I know there's diehards on Topband in the northern hemisphere
> that work CW DX on 160 all year long. I would like to know what
> they do to hear the weak ones in the southern hemisphere, in
> spite of the static crashes in North America's spring and summer.
>
Twofold "problem" - fewer stations south and direction of summer QRN also from
south, around equator. We get now shorter openings in the north, but following
the grey line and quiet nights offer some surprises, but definitely fewer then
those long winter nights here.
> I have an MFJ-1025, which I was thinking of using to try and
> reduce the QRN from distant lightning storms in North America,
> hoping to hear weak DX. Perhaps use the Inverted-L Tx antenna as
> the noise antenna, and the Beverages as the signal antennas,
> input to the MFJ-1025? However, what I've read seems to imply
> that that would be a waste of time. (Would it?)
>
By placing the null on the interfering QRN you can minimize it, but it is not
that simple, the area from which QRN is coming is quite large, so broad nulls
are needed. Play with various combinations and see what works in what situation.
Another important tool in minimizing the QRN is the use of direct conversion RX
(SDRs), low IF roofing filter rigs (K3, Ten-Tec, R4B) with simple crystal
filters. Multi pole filters and multiple filters in IF chain tend to stretch
the static crashes and pulses, making them longer and more annoying (like
pshhhhhttt vs. just psht)
> Or, are staggered and phased Beverages/BOGs a better way? Or,
> does one simply wait for good conditions? Perhaps summertime
> could use a different RX antenna than the Beverage. Maybe not.>
It boils down to trying to null or minimize the signals from the direction of
QRN, more antennas, more choice in finding the best configuration. QRN are
signals and quite broad, we are dealing with azimuth and elevation.
> Are we just going through a period of bad spring QRN, and it
> will get better in the summer?
It will get better when there are no storms. Seems that this sunspot cycle is
"blessing" us with plenty of storms, lightning during this loooong minimum.
> I would sure appreciate any advice and encouragement. I love
> 160, and I don't plan on simply waiting till November's quiet
> time and working other bands until then.
>
> 73 Mike
> W0BTU
Just hang in there and catch the good days, especially if they fall on contest
weekend. That is the challenge and pain of our lowest top band. It is much
worse closer to the equator.
73 Yuri, K3BU.us
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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