[CQ-Contest] The King (Packet cluster network) is dead! Long live the King (Skimmer reverse beacon network)

José Nunes CT1BOH ct1boh at gmail.com
Tue Jul 27 11:36:05 PDT 2010

When one looks at the growth of QSOs during 48 hour contests (notably
maximum QSOs in the CQWW SOAB CW category in the past decades:
50's 1277 QSOs
60's 2623 QSOs
70's 4505 QSOs
80's 5970 QSO
90's 7555 QSOs
00's 7828 QSOs
one has to wonder where have all those extra QSOs have come from.

- The operators have better resources and share more information (more
knowledgeable with propagation and openings, more skillful with SO2R
resources, ...)
- The logging software and Computer Generator CW have added extra efficiency
when working stations
- The stations (split TX signals) and low band antennas (both RX and TX)
have added extra QSO potential
       but If there is one aspect that has impacted Contesting the most, for
good or for bad, in my opinion, it is:
- The development of Packet Cluster network by AK1A in the late 80's and the
enhancement it has given to contest operators to be found while CQ'ing on a

There was one aspect in the Packet Cluster network that was not fair. Since
most users of the packet cluster network are DX'ers they tend to spot
stations more according to their DX rareness than to their actual operating

Looking at the packet spot data for 2009 CQWW CW with its almost 51.000
packet spots, listing the stations with most spots shows great differences
between them. Almost all these stations were active during the 48 hours of
the contest but still great differences exist:

For stations with most spots worldwide
HC8GR-573, LX7I-271 , EA8URL-254, JA3YBK-249, B7P-219, VK9XW-216, EE2W-211,
K3LR-206, KC1XX-206, JA5FDJ-198

For stations with most spots in the USA
K3LR-206, KC1XX-206, W3LPL- 165, K1LZ-156, K1TTT-155, NQ4I-139, W2FU-115,
NR4M-103, NR5M-99, K0RF-63

For station in the SOAB Category worldwide
V47NT-190, ZS4TX-183, A25NW-182, 8P5A-174, VE2IM-160, P49Y-146, 6W1RW-145,
EF8M-144, VQ5M-132, CR3E-127

There is not fairness in the packet cluster network. The more DX you are,
the more known you are the more spots you get, even if you have a great
signal or are QRV all the time. The K3LR verus K1LZ or V47NT versus EF8M
are good examples.

Another interesting aspect also to note is that more and more people rely on
the packet cluster network to work stations in contests.
Looking at 2009 CW Claimed results, there were 783 stations submitting logs
in the SOAB category and 1020 stations submitting logs in the SOAB Assisted
The fact that there is a majority of stations operating the Assisted
category versus the Non Assisted category in the SOAB class also provides
extra QSOs to those CQing stations, because in order to maximize QSOs these
Assisted stations are not only going after DX multipliers but also after
stations that are not necessarily multipliers for new QSO points.

In 2008 when VE3NEA - Alex Shovkoplyas developed CW Skimmer I sent him the
following note on Mar 2008:

"(...) you realize this is the end of CW contesting as we have known it. It
will be a very different contest in the future. (...) Also, with a script
that puts all the calls from CW Skimmer into packet, no need for "old
version packet". It's like having a requirement in the rules for self

What I did not realize was how quickly would Skimmer reverse beacon network
achieve such a degree of coverage and overcome Packet Cluster Network in a
devastating way.
The result can be tagged as "shock and awe" to use a military jargon.
In order for you to understand the degree of band coverage Skimmer reverse
beacon network is capable of I will compare the results of packet cluster
network performance against Skimmer reverse beacon network, using the last
IARU HF Championship contest as a reference and my CR3E operation.

I took the packet cluster network data from DX Summit Search option
http://www.dxsummit.fi/Search.aspx and Skimmer reverse beacon network from

CR3E was spotted 40 times in the packet cluster network. An average of one
spot every 36 minutes
CR3E was spotted 500 time in the Skimmer Reverse Beacon network. An average
of one spot every 2.9 minutes

The difference is incredible.
What is the impact of this difference? In order for all to fully understand
I will use the packet window concept.
Most Contest logging programs have a packet spot lifetime option to display
new multipliers and QSO's in the band map. Using a common 30 minute default
option, l can calculate the packet coverage of both the packet and skimmer
reverse beacon network.

Imagine CR3E started the contest on 15 meter and was QRV for 120 minutes on
that band.
Imagine there was only one packet spot during that 120 minute QRV and that
it occurred in the minute 20
CR3E will be in Assisted stations band map (if not worked) during the packet
spot lifetime window from minute 20 until minute 49 (30 minutes), when the
spots lifetime ends.
CR3E was QRV 120 minutes and there was a coverage of 30 out of 120 minutes,
i.e. 25% packet coverage for the time of QRV

So what is the difference between Packet Cluster Network (PCN) and Skimmer
Reverse Beacon Network (SRBN) for CR3E IARU operation when it comes to
packet coverage?

Looking at the 1440 minute of the IARU contest I checked how many minutes
CR3E was QRV while CQing/Running. I removed minutes with SO2R QSOs that are
not spotted because I'm replying to stations:

On 28 Mhz CR3E was QRV 68 minutes, there was a 65% PCN and 78% SRBN coverage
On 21 Mhz CR3E was QRV 485 minutes, there was a 60% PCN and 96% SRBN
On 14 Mhz CR3E was QRV 503 minutes, there was a 53% PCN and 98% SRBN
On 7 Mhz CR3E was QRV 283 minutes, there was a 33% PCN and 99% SRBN coverage
On 3.5 Mhz CRE was QRV 28 minutes, there was a 86% PCN and 96% SRBN coverage
On 1.8 CR3E did not CQ, just S&Ped.

Skimmer Reverse Beacon Network (SRBN) achieved an incredible 96% window
coverage. while CR3E was CQ/running. i.e. CR3E was spotted ALL the time of
the contest, whenever he was CQing (TEST CR3E). To put it in another way the
minute I CQ the minute a Skimmer Robot will spot me.
There was even one time Skimmer reverse beacon network spotted me before I
even logged stations.

With Skimmer reverse beacon network, spotting will rely on robots. Everybody
will be spotted about the same for same conditions. It's democracy into
packet spots.

t's no wonder stations like K3LR have implemented their won skimmer network
http://www.k3lr.com/skimmer/ in order to have all the data of active
stations on the bands, in order to gain an extra competitiveness over their
competitors. Tim K3LR told me that last ARRL they even found a new opening
never heard of, thanks to skimmer.

Assisted stations, MS, M2, MM, DXers and alike don't need systems like K3LR
to gather all this data. They can feed into the telnet aggregated output of
all currently active skimmer reverse beacon receivers in real time at
telnet.reversebeacon.net port 7000. Check
 http://reversebeacon.blogspot.com/ for details.

Relying in the old Packet cluster network is the best way to loose. Relying
into Skimmer reverse beacon network is the way for Assisted station in CW

I guess it is proper to say The King (Packet cluster network) is dead! Long
live the King (Skimmer reverse beacon network).

I have never operated in the Assisted SOAB class in my 36 CQWW Contests as a
single operator that span over 21 years non stop since 1989.
I do recognize the great impact packet has had in my pile-ups and
operations. I do love packet pile-ups. "It's rush after rush". Packet
spotting is certainly here to stay, no matter what.

Will the contest be a different one? Information is tilting the nature of
the contest. It will not be worse nor better. It will be just different. And
I guess change is what people fear the most.

John F. Kennedy once said "Change is the law of life. And those who look
only to the past or present are certain to miss the future."
I don't really care if the good old days are better than today but it is an
interesting coincidence that for some, the less days one has left the better
the good old days are...

José Nunes
CONTEST CT1BOH - http://www.qsl.net/ct1boh

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