Very interesting analysis and obviously a LOT of effort went into this. Reading
this, a few thoughts
occured:
1. Did the guys at PT5M also have a 40m terrain advantage over others (PW5X,
for example) in top
five? Top ten?
2. If the terrain profile to the USA is an advantage on 40m, isn't it also an
advantage on the
higher bands?
3. From the coordinates given, it appears PT5M is almost 200km North of PW5C.
Could this also
account for a much different propagation to USA on 40m?
4. HFTA's angles are averages over solar cycles, months, etc. It would be
interesting to generate
arrival angles based on actual solar data for the period of the contest and
re-run the analysis.
Jose, thanks for an interesting perspective on the differences in the top two
scores.
Congratulations on your first child!! Hope mother, child..and dad..are doing
well.
73, Ted W4NZ
-----Original Message-----
From: cq-contest-bounces@contesting.com
[mailto:cq-contest-bounces@contesting.com]On Behalf Of José Nunes CT1BOH
Sent: Saturday, August 19, 2006 9:39 AM
To: cq-contest@contesting.com
Subject: [CQ-Contest] Why did the Canadians (PT5M) beat the Americans
(PW5C)in WRTC 2006?
Why did the Canadians (PT5M) beat the Americans (PW5C) in WRTC 2006?
The answer to this question is actually quite simple: Not enough Americans
worked PW5C on 40 meters. No, it was not a national boycott to the American
team by their fellow compatriots as you will see below…
After reading the answer to the first question I will just ask one more
question:
Do we need a handicap system for WRTC's?
The 2006 WRTC is over and done, and to start with I think it is not enough
to say the PY's did a FANTASTIC job. I repeat a FANTASTIC job. Although I
was not able to attend, because of my first child birth, everyone who was
there and I talked to had nothing but praise words to the incredible effort
put up to make WRTC 2006 the best WRTC so far.
I worked the event from home and followed with particular interest the hour
by hour live scoreboard and the battle between the first two teams PT5M
(VE3EJ + VE7ZO) and PW5C (N6MJ and N2NL) with PW5C leading the first hours
and then a turn around with PT5M claiming victory.
With all the logs available on WRTC official web site I retrieve these two
and begun analyzing them to try to explain why such a turn around in the
last hours of the event.
Just looking at raw QSO data, plotting the difference of QSO's between PW5C
and PT5M, it is interesting to note that the difference in QSO's between the
two was always up and down between 0 and around 50 QSO's from the start of
the contest at 12:00z the first day until 03:00z the second day (note: the
Americans were leading in score because they had a better multiplier total).
At 03:00z the difference between the two teams was just two (2) QSOs. After
03:00z until 10:00z the Canadians gained about 215 QSOs. After 10:00z and
until the end of the contest at 11:59 again there was not much difference in
the effort of the two teams to work QSO's. The edge the Canadians gained in
QSO's during 7 hours of the contest (03:00-09:59z) eventually was enough to
overcome their multiplier disadvantage and win the event.
The astute readers will realize one very important fact to explain why the
answer to the first question is so simple: propagation on 40 dies between
PY5 and Europe around 03:00Z as all the logs demonstrate it. 20 meters was
dead and 80 was not productive. All there was to work was USA and the
American continent, as the rest of the world QSOs was negligible. Repeat
there was no Europe to work as all the logs show it. It is also important to
note that after 10Z with sunrise approaching contesters tend to move to the
high bands.
Click the link below to see the graph (at 13:24 for instance a value of -43
means PW5C is 43 QSO's behind PT5M)
http://ct1boh.planetaclix.pt/wrtc/pt5mvspw5c.JPG
Wow! What happened in those 7 hours between 03:00z and 09:59 that dictated
the final outcome of the WRTC 2006 winner?
During those 7 hours both stations were on the low bands (mainly 40 and
occasionally on 80), but their efforts netted very different results, and
the key element is the fact that because of propagation characteristics in
Brazil and the low part of the sunspot cyle, the contest during those 7
hours turned basically into a 40 meter/USA only event.
Let's check PT5M QSO's 03:00 – 09:59z
20 meters: 2 QSO's
40 meters: 477 QSO's
80 meters: 56 QSO's
Looking for 40 meters the continent distribution was:
Europe 8 QSO's
Japan 20 QSO's
Other 97 (basically North and South America) QSO's
USA 352
Let's now check PW5C QSO's 03:00 – 09:59z
20 meters: 0 QSO's
40 meters: 272 QSO's
80 meters: 50 QSO's
Looking for 40 meters the continent distribution was:
Europe 3 QSO's
Japan 5 QSO's
Other 62 (basically North and South America) QSO's
USA 202 QSO's
During these 7 hours, while on 40, the Canadians ended up working a lot more
QSO's and those QSO's were the difference to their victory against the
Americans.
And what were the state side boys doing these hours? Well they couldn't do
much, they were crying like babies but mom and daddy did not come to feed
them…They were calling CQ, CQ, CQ, CQ,CQ and getting not many answers.
Let's check for every one of these 7 hours, how many minutes each team had
with 0 (zero) QSOs:
Hour PT5M PW5C
3z 10 21
4z 11 32
5z 17 22
6z 12 15
7z 22 37
8z 30 42
9z 24 41
Total 126 210
In these 7 hours the state side boy's team had 210 minutes with zero QSOs,
and I bet they were not sleeping or taking a time way to pee….
If we now look to the minutes with QSOs we can check that the Canadians had
294 minutes with QSOs – 535 QSOs at a rate of 1,82 QSOs per minute and the
Americans had 210 minutes with QSOs – 322 QSOs at a rate of 1.53 QSOs per
minute, i.e. the Canadians were working stations faster and at least two
levels of stations PW5C could not work or copy as we will see why ahead in
the text below.
Now if you remember, in the first 15 hours of the contest both teams worked
almost exactly the same number of QSOs:
PW5C 1757 QSOs and PT5M 1759 QSOs
So if these two teams had such similar performances why such a difference
now on 40?
The answer is LOCATION/TERRAIN and LOW ANGLES…
With latitude and longitude coordinates of both locations PW5C 27 44 20S, 48
30 41W, PT5M 26 08 52 S, 49 10 47 W) and Google Earth it is possible to
check the PY5 – USA path from the two sites, and use the terrain data to
analyze the take off angles of the signals using HFTA (N6BV great
program).. For this analysis I used the PY1 to US data available in the ARRL
Antenna Book CD.
Click below to see the terrain characteristics of both teams toward USA and
the figure of merit of the two antennas on 40 taking into account the
terrain and the angle information of the signals between PY5 and the whole
of USA.
Terrain graphs:
http://ct1boh.planetaclix.pt/wrtc/pt5m_pw5c_terrain.JPG
Image of view of PT5M towards USA:
http://ct1boh.planetaclix.pt/wrtc/pt5m_usa.jpg
Image of view of PW5C towards USA:
http://ct1boh.planetaclix.pt/wrtc/pw5c_usa.jpg
Figure of merit of antennas taking into account terrain:
http://ct1boh.planetaclix.pt/wrtc/pt5mvspw5c_fom.JPG
What's so interesting about these graphs?
To start PT5M had a geographical location advantage towards USA over PW5C.
Now let's check the low angles and the antenna performance (Dbi) according
to the terrain data:
First, PT5M 40 meter antenna/terrain has a FOM (figure of merit) of 6.9 DBi
compared to 4.7 DBi of PW5C. Those 2.2 DBis open a level of stations.
Second looking at the very low angles, surely used by signals for this part
of the cycle we have:
Angle PT5M PW5C
1 -3.7 -7.0
2 1.2 -2.0
3 3.4 -0.6
4 4.4 -0.9
5 5.4 -1.6
6 5.5 3.4
7 3.8 3.9
8 4.9 4.3
>From 1 to 6 degrees on average PT5M is 4.15 DBi better than PW5C. It's two
levels of stations.
PT5M beats PW5C all the time in the low angles, and these zero to eight
degree angles represent statistically 34% of the incoming signals.
No wonder PW5C is about 40% down on QSO's on those 7 hours against PT5M.
It is clear to me Location/Terrain was the factor for N6MJ/N2NL loosing all
those QSO's during those 7 hours on 40/80 between 03:00 and 09:59z.
Note I'm not saying N6MJ/N2NL should have been the winners, although I have
my own thoughts. We do not know what their performance would be at the
command of PT5M on those 7 hours. Nor we know what VE3EJ/VE7ZO would do at
the command of PW5C from 12:00 to 03:00z and then from 10:00 to 11:59z. But
the fact remains that PW5C lost ground and eventually the contest because of
what happened from 03:00 to 09:59z on 40 meters.
Anyway, what is all this about?
Well it is clear that WRTC is not a plain level field event!
I just looked into two stations but I'm sure a lot more differences exist,
and unless everyone goes to the flatlands of Russia , or to BS7H rocks with
verticals probably no WRTC will be even, unless a handicap system is
developed. We have the technology to adjust each location to it's true radio
potential, using programs like HFTA. Perhaps then, with a handicap system,
WRTC will truly measure team operator performance.
73
José Nunes
Contest CT1BOH - www.qsl.net/ct1boh
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