Hi Jose,
You wrote: There is no need for propagation prediction anymore because,
knowing the propagation pattern from 20 billion spots and getting real
propagation fromthe 22 million spots per day, real time conditions come from
now-casting propagation - any circuit can be determined to be open or close.
Can you tell me the geographic distribution of those 22 million/day spots?
Much of the world is dark. I'm on FT8 every day, using PSKReporter via
ViewProp for spots, which are shown on the N1MM+ bandmap and DX Atlas. The
view every day is the same: lots of EU and NA, some SA, a few AF (mostly CT9,
EA8, maybe ZS), a few Middle Eastern AS, some Far Eastern AS (JA mostly), very
few OC except some VK/ZL. That's it.
I don't believe that gives me a good grasp of worldwide propagation. I rely
on it as you suggest, but also take propagation into consideration with HamCAP
or VOACAP. I jack up my HamCAP power parameter to 1000w to account for FT8
efficiency (I run 100w to simple wires).
If I want to know if there are openings to Mauritius or Tahiti, FT8 won't tell
me as there is no appreciable operation from those QTHs. I've not worked
either on an FT mode.
73,
Ken, AB1J
-----Original Message-----
From: José Nunes CT1BOH <ct1boh@gmail.com>
To: cq-contest@contesting.com
Sent: Sat, Jun 19, 2021 3:24 pm
Subject: [CQ-Contest] Contesting and the FT8 Revolution
There is a revolution going on – The FT8 revolution! Like other
revolutions, it is a breakthrough and there is no coming back. But unlike
what many think, FT8 mode is fantastic for amateur radio and of course for
contesting.
There are several things I can particularly note:
** The spotting revolution
Because of the default reporting option of FT8 applications, every station
that uses JTDX/WSJT applications is constantly spotting all the stations
that the decoders hear. Every station becomes a spotting machine of the
bands (just like a skimmer) while they are on. The result?! 20.8 billion
FT8 spots in 4 years.
** The small pistol station revolution
Considering a 2500 Hz bandwidth and weak-signal/Noise Ratio, SSB can go as
low as +10 dB, CW -15 db and FT8 -21dB. To put it in another way, since
doubling power results in 3 dB increase in SNR, a 31db difference means 1W
in FT8 versus 1024 watts in SSB.
A modest station, suddenly, feels like a new world of propagation has
opened to him and this in return brings more and more people to the bands
because of the fun of working stations and paths not before available.
There is a virtuous cycle – more spots, more people, more activity, more
spots, more people, more activity, …
** The now-casting propagation revolution
With such a huge volume of spots, 20.8 billion in 4 years and around 22
million spots per day [just for your reference last CQWW CW generated 6.5M
spots], propagation prediction is turning into now-casting propagation.
There is no need for propagation prediction anymore because, knowing the
propagation pattern from 20 billion spots and getting real propagation from
the 22 million spots per day, real time conditions come from now-casting
propagation - any circuit can be determined to be open or close.
You can watch my 2021 Contest University presentation about this subject
here https://www.youtube.com/watch?v=q-esob7BPtc&t=20340s and/or get the
slides of the presentation slides here
https://www.contestuniversity.com/wp-content/uploads/2021/05/There-is-Nothing-Magic-About-Propagation-CTU-2021-CT1BOH.pdf
** The station optimization revolution
This is perhaps one of the most overlooked aspects of FT8 and of great
interest to contest stations. Because of the spotting revolution and
because every FT8 station uses exact grid locator, the exact path of the
circuits can be drawn. A contest station that uses a simple FT8 skimmer can
monitor, 24x7, the potential of any antenna set-up, compare different
antennas configuration (A/B testing using different calls), test antenna
take-off angles, and adjust this information to available propagation at
any time, before or during a contest. “22 million spots per day” are there
available to test your station. I believe every station, DX or Contest, should
use a FT8 Skimmer, like the stand alone Red Pitaya
https://www.redpitaya.com/ to skim several bands at the same time at a very
low cost, provide now-casting information, check antenna and location
potential and use that for station optimization. This link takes you to a
visualization of my modest small pistol station (just a simple long wire)
potential on all the bands https://tinyurl.com/e6767we8 in the last 24
hours.
** The marginal bands revolution
With FT8, marginal bands like 160, 10 and 6 meters become alive like no
other. Going deeper into the SNR, “opens” new circuits, brings more
activity, confirms these circuits were always there. We are working Japan
on 6 meters on a daily basis... Also, there is a move from CW into FT8 on
these band. This is a side effect, but it is what it is. If people suddenly
find a band open at -21dB that before was close at -15dB, of course they
will use the mode that enables those QSOs and will not use the other mode
anymore.
In any case competitive contesting (SSB and CW) has a lot to gain form this
revolution. Exciting times indeed
73 José Nunes
CONTEST CT1BOH - http://www.qsl.net/ct1boh
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