Most-Logged Stations in CQ WW CW and SSB Contests: 2021, and the decade from 2012 to 2021


The public CQ WW CW and SSB logs allow us easily to tabulate the stations that appear in the largest number of entrants' logs. For 2021, the ten stations with the largest number of appearances in CQ WW SSB logs were:

Callsign Appearances % logs
LZ9W 10,680 55
EW5A 10,233 55
YT5A 10,164 54
M6T 10,031 54
PJ2T 9,768 46
ES9C 9,672 54
DF0HQ 9,361 52
A73A 9,329 50
EI7M 9,050 49
CR6K 9,016 49

The first column in the table is the callsign. The second column is the total number of times that the call appears in logs. That is, for example, if a station worked LZ9W on six bands, that will increment the value in the second column of the LZ9W row by six. The third column is the percentage of logs that contain the callsign at least once.

Similarly, the ten stations with the largest number of appearances in CQ WW CW 2021 were:

Callsign Appearances % logs
TK0C 14,707 73
CR3W 12,889 69
CR3DX 11,513 66
LZ9W 11,363 67
M6T 11,055 65
RW0A 11,009 61
PJ2T 10,953 57
PJ4K 10,639 61
YT5A 10,433 64
ES9C 10,303 62

Note the substantial difference between the SSB and CW tables.

I find it interesting to see which stations have had the most long-term activity on the contests. For the ten years from 2012 to 2021 on SSB we find:

Callsign Appearances % logs
LZ9W 91,773 55
DF0HQ 82,643 53
CN3A 75,722 47
PJ2T 69,813 41
K3LR 67,138 45
A73A 64,454 43
P33W 63,731 43
OT5A 63,701 42
HG7T 60,538 43
TM6M 58,986 42

And for the same years on CW:

Callsign Appearances % logs
LZ9W 104,503 66
PJ2T 89,627 51
9A1A 86,922 54
P33W 80,440 52
DF0HQ 78,211 53
W3LPL 71,848 47
ES9C 71,104 46
LZ5R 70,921 53
K3LR 70,279 47
YT5A 69,422 49


Unofficial Station Reports, CQ WW SSB and CW, 2005 to 2021


Using the public logs, it is rather easy to generate unofficial station-by-station reports for the entrants in the CQ WW contests.

The contest committee generates official reports and generally sends these reports individually to each entrant. But these are typically not made public (although there are some exceptions). The unofficial reports, while not necessarily identical to the official ones, may hold some interest.

The unofficial reports may differ from the official ones because the contest committee has access to checklogs, which are not made public. Also, there are various pathological occurrences in logs that require a decision to be made as to how to classify one or more QSOs; the rules by which such decisions are made are not public, so the decisions that I made when constructing the unofficial reports may well be different from those made by the contest committee. Nevertheless, pathological logs (or pathological QSOs within a log) are relatively rare, so these decisions should affect a relatively small percentage of logs and QSOs. (Typical examples [there are many more] of circumstances in which decisions must made be are: by how much may clocks be skewed and a QSO still be considered valid? what to do if the transmitted callsign changes for some number of QSOs in the contest? what do to if more than one entrant claims to have used the same transmitted callsign?)

The complete set of unofficial reports for the CW and SSB versions of the CQ WW contest for the years 2005 to 2021 may be found in appropriately named files in this directory.


Cleaned and Augmented Logs (including RBN data) for CQ WW CW and SSB Contests, 2005 to 2021

Cleaned and augmented versions of the logs for the CQ WW CW and SSB contests are now available for the period 2005 to 2021.

Links to the cleaned and augmented logs may be found in this directory (look for "clean" or "augmented" in the filenames).

The cleaned logs are the result of processing the QSO: lines from the entrants' submitted Cabrillo files to ensure that all fields contain valid values and all the data match the format required in the rules. Any line containing illegal data in a field (for example, a zone number greater than 40, or a date/time stamp that is outside the contest period) has simply been removed. Also, only the QSO: lines are retained, so that each line in the file can be processed easily. All zones are rendered with two digits, so as to further simplify processing by scripts or programs.

The augmented logs contain the same information as the cleaned logs, but with the addition of some useful (derived) information on each line. In addition to the actual logs, two additional sources of information are used when appropriate:

  1. AD1C has made accessible historical cty.dat and associated files. These allow us to use callsign-based multiplier lists as they would have existed at the time of each contest.

  2. From 2009 onwards, the Reverse Beacon Network (RBN) has been available for the CW contests. This allows us to include the time since a station was last posted by the RBN (see below for details).

The information added to each line of the augmented logs comprises:
  1. A sequence of four characters that are the same for each entry in a particular log:
    •  a. letter "A" or "U" indicating "assisted" or "unassisted"
    •  b. letter "Q", "L", "H" or "U", indicating respectively QRP, low power, high power or unknown power level
    •  c. letter "S", "M", "C" or "U", indicating respectively a single-operator, multi-operator, checklog or unknown operator category [ the contest organisers have stated that checklogs are not made public, but in fact at least some of them from the early years have been, hence the need for the "C" category ]
    •  d. character "1", "2", "+" or "U", indicating respectively that the number of transmitters is one, two, unlimited or unknown
  2. A four-digit number representing the time if the contact in minutes measured from the start of the contest. (I realise that this can be calculated from the other information on the line, but it saves subsequent script-based processors of the file considerable time to have the number readily available in the file without having to calculate it for each QSO.)
  3. Band
  4. A set of fourteen flags, each -- apart from column k and column n -- encoded as T/F: 
    • a. QSO is confirmed by a log from the second party 
    • b. QSO is a reverse bust (i.e., the second party appears to have bust the call of the first party) 
    • c. QSO is an ordinary bust (i.e., the first party appears to have bust the call of the second party) 
    • d. the call of the second party is unique 
    • e. QSO appears to be a NIL 
    • f. QSO is with a station that did not send in a log, but who did make 20 or more QSOs in the contest 
    • g. QSO appears to be a country mult 
    • h. QSO appears to be a zone mult 
    • i. QSO is a zone bust (i.e., the received zone appears to be a bust)
    • j. QSO is a reverse zone bust (i.e. the second party appears to have bust the zone of the first party)
    • k. This entry has three possible values rather than just T/F:
      • T: QSO appears to be made during a run by the first party
      • F: QSO appears not to be made during a run by the first party
      • U: the run status is unknown because insufficient frequency information is available in the first party's log
    • l. QSO is a dupe
    • m. QSO is a dupe in the second party's log
    • n. RBN information (see below)
  5. If the QSO is a reverse bust, the call logged by the second party; otherwise, the placeholder "-"
  6. If the QSO is an ordinary bust, the correct call that should have been logged by the first party; otherwise, the placeholder "-"
  7. If the QSO is a reverse zone bust, the zone logged by the second party; otherwise, the placeholder "-"
  8.  If the QSO is an ordinary zone bust, the correct zone that should have been logged by the first party; otherwise, the placeholder "-" 

RBN Information

In the CW contests from 2009 onwards, the RBN was active, automatically spotting the frequency at which any station calling CQ was transmitting. To reflect possible use of RBN information, the augmented files now include a fourteenth flag. For the sake of uniformity, this column is present in all the augmented files, regardless of whether the RBN actually contributed useful information to a particular contest.

Each QSO has one of several characters in the fourteenth column of flags. These characters should be interpreted as follows:

  No useful RBN-derived information is available for this QSO.

  The worked station (i.e., the second call on the log line) appears to have begun to CQ on this frequency within (roughly) 60 seconds prior to the QSO.

'A' to 'Z'
  For the nth letter of the alphabet: the worked station appears to have been CQing on this frequency for (roughly) n minutes prior to the QSO.

  The worked station appears to have been CQing for more than 26 minutes on this frequency.

  Because the the RBN is distributed, and because each contest entrant station has its own clock, there is generally a skew between the reading of the clock of the station making the QSO and the timestamp from the RBN at which it believes a posting was made (indeed, it's unclear from the RBN's [lack of] documentation exactly how the timestamp on an individual RBN posting is to be interpreted). If the character '<' appears in the the RBN column, it indicates that the raw values of the clocks suggest that the QSO took place up to two minutes before the RBN reported the worked station commencing to CQ at this frequency. When this occurs, the most likely interpretation is that there is non-negligible skew between the two clocks, and the station was actually worked almost as soon as a CQ was posted by the RBN. This character also appears if the RBN erroneously posts the worked station as CQing at this frequency shortly after the QSO. But it might also mean that the entrant was simply lucky and found the CQing station just as it fired up on a new frequency.

  • The encoding of some of the flags requires subjective decisions to be made as to whether the flag should be true or false; consequently, and because CQ has yet to understand the importance of making their scoring code public, the value of a flag for a specific QSO line in some circumstances might not match the value that CQ would assign. (Also, CQ has more data available in the form of check logs, which are generally not made public.)
  • I made no attempt to deduce or infer the run status of a QSO in the second party's log (if such exists), regardless of the status in the first party's log. This allows one cleanly to perform correct statistical analyses anent the number of QSOs made by running stations merely by excluding QSOs marked with a U in column k.
  • No attempt is made to detect the case in which both participants of a QSO bust the other station's call. This is a problematic situation because of the relatively high probability of a false positive unless both stations accurately log the frequency as opposed to merely the band. (Also, on bands on which split-frequency QSOs are common, the absence of both transmit and receive frequency is a problem; I confess that I have never understood why Cabrillo was not designed to report both transmit and receive frequencies -- or even to define clearly which frequency is to be reported. I digress.) Because of the likelihood of false positives, it seems better, given the presumed rarity of double-bust QSOs, that no attempt be made to mark them.
  • The entries for the zones in the case of zone or reverse zone busts are normalised to two-digit values.


CQ WW Video Maps: 2005 to 2021


I have updated the set of CQ WW video maps on my youtube channel (channel N7DR). These video maps cover all the years for which public CQ WW logs are currently available (2005 to 2021).

To access individual videos directly:

The videos are created with time steps of ten minutes; when playing the video, each time step is displayed for five seconds. The videos are presented as animated GIF files, so they should display correctly without any specialised video software installed on your computer.

The videos assume that all communication is via the great-circle short path route, and include only inter-zone contacts. The width of the arcs is an absolute measure of the number of QSOs taking place over that path in the particular 10-minute segment. The colour of the arc reflects the relative number of QSOs taking place over the path. Each separate image (i.e., 10-minute segment) is normalized so that the path with the greatest number of QSOs is rendered in white. Paths with fewer QSOs are in progressively darker colours. Thus, arc colour should not be compared from one still image to another; arc width, however, is meaningful. The width of an arc in pixels is one plus the natural logarithm of the number of QSOs represented by the arc.


Debian Bullseye, Samba and WIndows XP

Following an upgrade here from Debian Buster to Bullseye, I discovered that a Windows XP computer on my home network could no longer access a samba share on the upgraded system, even though (or possibly because, although I doubt it) I did not allow the upgrade to change the /etc/samba/smb.conf file. After a bit of messing around, I discovered that the solution is easy, although apparently undocumented as yet, at least officially. I added the line:

server min protocol = NT1

to the [global] portion of the file, and then restarted samba:

systemctl restart smbd.service

From that point on, I found that the XP machine was once more able to reach the samba shares correctly.

I note that the inability to browse Bullseye samba shares from XP machines that previously could browse Buster shares on the same server machine has been reported as Debian bug 948671, with the above workaround now documented in an associated submission by me.