K5ZD Log checking

SDR Recordings Help with Log Checking

The new generation of Software Defined Radios (SDR) has the ability to cover wide frequency ranges and record all of the activity within that range.  This digital data can be spooled to disk for storage and transport. Other software allows the user to go back and “tune” through the recording by frequency and time.  It is just like listening to a replay of the contest as it happened over the air!

The CQ WW Contest Committee has used SDR recordings in the past to assist with the log checking. It is incredibly valuable for us to be able to go back and listen “live” to what happened at the time and frequency shown in the logs.

Lead by Steve Bolia, N8BJQ, the committee made a much greater effort to collect and use SDR data for checking the 2012 contests. SDR recordings of the complete SSB and CW contests for 2012 were made at 9 sites in Europe, North America, and Oceania. The following stations volunteered their SDR setups to make recordings:

  • ES5PC
  • OH6LI and OH6BG
  • HA1AG with HG6N guys
  • S50XX and S52X
  • WZ7I
  • N4ZR
  • N6TV
  • KH6LC
  • ZL2HAM

Having so many locations provided very good coverage of all of the contest bands and most of the world.  There are a few gaps which we are looking to fill in for the 2013 contest season.

Before the contest SKYPE messenger was used by the recording stations to work out the technical details of collecting the data using CW Skimmer software (for CW), a QS1R receiver, and OL5Q’s CWSL software.  This required lots of tweaking of settings, some software changes, and test recordings, but all was finalized the week before the contest.  All of the SDR clocks were synced to a time standard.

During the contest each site collected approximately 1.3TB of data on USB portable hard drives.  The US stations and ZL2HAM mailed their drives to N8BJQ who copied the data and returned the drives for use in the next contest.  Each drive took about 17 – 18 hours to copy!  All drives made the two-way trip with no problems.  The European SDR sites transferred data using FTP to one or two sites.  That took a couple of days for each contest.

Once the recording data was on hand, S50XX, CT1BOH and N8BJQ supported the log checking team by providing recordings of log segments or QSOs as requested.  The recordings were used to help check for things such as band change violations for Multi-Op stations, not In log checks, single op stations using more than one operator, stations having two signals on the air at the same time, stations working outside of their band, and some signal strength comparisons.

Two examples will illustrate how valuable the SDR data can be. The multi-single and multi-two categories have very specific rules about how many transmitted signals can be used and when band changes may occur. The SDR gives the committee the ability to know exactly what time a QSO was made and on what band. We are also able to listen to multiple frequencies at the same time. This lets us check if a station is transmitting more than one signal on a band. We were very impressed at how well some of the top multi-op teams stay within the rules!

Thanks to N8BJQ, S50XX, CT1BOH, and the SDR team for their help to make the CQ WW DX Contest results as accurate as possible. If you would like to join the recording team, please contact Steve, N8BJQ at n8bjq@cqww.com for more information.

 

K5ZD Announcements, CW

CQ WW CW Raw Scores Available

The raw scores for CQWW CW 2012 are now available at http://www.cqww.com/claimed.htm?mode=cw

These are scores calculated by the log checking software before any cross checking is performed. Scores could change between 2-20% depending on the accuracy of the operator.

Please check that your entry is in the correct category. Report any errors or questions to questions@cqww.com.

The raw scores for SSB have also been updated to include some late arriving logs.

K5ZD Log checking

Logging Time and Other Things

The CQWW Phone Contest for 2012 had over 5.2 million QSOs in the more than 8000 logs that were submitted. It takes over 45 minutes to run the log checking software up in the Amazon EC2 Cloud Computing environment. That’s a lot of processing!

A big part of the log checking is to verify each QSO against the other log. Can we find a matching call sign within a time window of when the QSO was logged? In 95% of the cases we do and the points are confirmed. The other 5% of the time, the software must look for other call signs that are off by 1 letter or off by 2 letters. It is amazing how well the computer is able to find a probable match and determine the error.

The concept of a “time window” around the logged QSO time is very important in this process. It is not enough that both stations have the call sign in their log on the same band. They must both have it logged within a window of +/- 15 minutes. If they don’t the computer has no way of knowing that a valid QSO actually occurred and must assign a NIL.

Let’s look at two real-world examples.

Example 1. There were two multi-single stations that reported a QSO with each other in their logs. One had the QSO on day 1. The other had the QSO logged on day 2. Did a valid QSO actually happen? In our opinion, it did not. Because there was no matching call sign in the other log at the time of the QSO, we had no choice but to declare this a Not-In-Log (NIL), which includes a 3x penalty. In this case both stations lost the QSO and the multiplier.

Example 2. One station logs contacts at the correct time. Another station has their clock off by 45 minutes. These QSOs do not match in each log within the time window and therefore both stations are assigned a NIL. It’s a tough break for the station that did everything right, but there is really no way for us to know the QSO actually occurred. It is required that both stations correctly log the QSO including the time! (The log checkers do try to detect these types of time errors that occur across a log and correct them, but proper logging of QSOs remains the responsibility of the entrant.)

Recommendations

  • Check the clock on your PC before the contest and make sure the log is recording the correct time in UTC. And that the time remains correct throughout the entire contest! (If your PC clock drifts, take a few minutes to periodically correct it.)
  • Log all dupes. If a NIL happens because one side did not log the QSO, the dupe contact may check valid and give both of you credit for the contact (and multiplier).

Exchange Errors

The log checking software does check for correctly logged zones. You need to make sure you copy what the other station says during the exchange and not just trust your logging software to fill in the zone number. This is especially true when working USA stations where the call sign may not correctly indicate the actual location. A good example is working a W6 who lives in Florida and recording zone 3 in your log. If we receive a log from the W6 and see the zone error during the checking, you will lose credit for the QSO.

There is one very popular software package that does not always correct the zone number when the call sign is edited. This can result in zone 35 being assigned to a station in Germany or 13 being assigned to a station in Japan. This will result in a lost QSO when we do the checking. Before you hit the enter key, take a moment to check that the zone in your log matches the call sign!

Errors are a natural part of the game and something to learn from. We want you to keep every point you have earned over the air. The best way to do that is take a little extra care in logging the time and zone information in your log during the contest. The rules prohibit using outside sources or databases to go back after the contest and correct your log.

 

K5ZD Announcements

EA4KD Joins CQWW Committee

I am pleased to announce that Pedro Vadillo, EA4KD, has joined the CQWW Committee.  Pedro has assisted with the WPX Contest in the past and is an avid contester.

Licensed in 1984, Pedro enjoyed VHF contesting before he discovered his first CQWW SSB in 1993 — he has continuously participated every year since. He has also participated in every edition of the CQWW CW since 2003. He has several EA records in the CQWW. Pedro normally participates as single operator but has also been part of several multi teams: EA4URE, EA4ML, EA9EA, EE2W and EC2DX, among others. Apart from contesting, he has been a DXCC Card Checker since 2001 and writer of the DX section of the Spanish magazine “CQ Radio Amateur” since February 2006.

Activity from Spain is growing and the CQWW Committee needed a representative in this area who could help with communication.

Pedro’s email is ea4kd@cqww.com.