Short answer: In a long contest, logging errors are not spread evenly across the hours. They tend to gather in the night, when the operator is tired, the low bands are noisy and the signals are weak. You can usually see the pattern after the contest by comparing your hourly statistics with the QSOs you had to correct. The remedy is not heroism but planning: rest before the worst hours, work a little slower when accuracy drops, and always ask for a repeat when a call or an exchange is in doubt.
The pattern behind the errors
Experienced contesters tend to tell the same story. The first hours of a contest are clean, the middle is busy, and the log is full of small problems around the middle of the night. It is not that the operator becomes careless, but that several things happen together. Human attention follows a daily cycle with a low point in the early hours of the morning. At the same time, the bands that carry the contacts at night, usually the lower ones, bring weak signals, atmospheric noise and heavy interference. And by the second night of a 48-hour contest, the operator has already spent many hours at the desk.
Each factor makes a mistake more likely. Together they multiply. A tired operator hears less well, takes more risks with partial calls, types more slowly and corrects less. The result is a log in which the busted calls, missing characters and wrong numbers come more often in the same stretch of hours.
The usual suspects at night
- Weak signals. On the low bands, the stations you are working are often at the limit of readability. A character lost in the noise becomes a guess.
- Interference and noise. Static crashes, a neighbour’s noise and strong adjacent stations make copying harder and increase the chance of a partial copy.
- Autopilot. After many hours, the exchange feels automatic, and the operator stops listening to what is really being said. Numbers and zones are filled in from habit.
- Reliance on the logger. A tired operator may accept the logger’s suggestion because it looks right. If the real station sent something else, the log ends up with a plausible but wrong call. The article on call history files describes the same risk.
- Typing errors. Fatigue slows reactions and increases slips of the fingers, such as a doubled or missing letter.
- Distraction and fragmentation of attention. With long sessions, people check their phone, talk, eat or do other things while operating, and the quality of the work drops.
The article on busted callsigns lists the common causes in more detail. What the night adds is the concentration of those causes into a few hours.
How to see it in your statistics
The statistics do not show errors directly, but they show the conditions in which errors occur. Look at the QSOs by hour and by band, and at the rate. These signs may point to a risky hour:
- A falling rate with the same effort. If the rate drops in the hours after midnight while the band was open, the operator may have slowed down because of fatigue or difficulty in copying.
- A sudden jump in activity. A very high rate in the middle of the night can be a good run, but it is also the time when speed is traded for accuracy.
- Many dupes and repeated calls in a few hours. Working the same station again by mistake is a sign that the operator lost track. It is not an error, as dupes are not errors, but it is a signal of fatigue.
- Breaks and off time. A long break just before the weak hours means rest, and a missing break means a tired operator. Your statistics show your breaks and off time.
The most reliable way is to add your own data. When you review the log and correct a callsign or an exchange, write down the time of the QSO. After a few contests, you will see which hours produce the corrections. The sheet view and the way to read gaps and peaks are described in the article on hour-by-hour analysis of a contest log.
Using the review to find the weak hours
Contest Analyzer checks every callsign and every zone against official license databases and several independent reference sources and shows only the few QSOs worth a second look. Treat the list as a map of where your log is least certain. For each QSO you decide to edit, make a note of its time. Do not draw conclusions from a single case; look for groups. If four of the six QSOs you corrected were made between local midnight and the early morning, you have found your weak window. The report also gives full statistics, with rates, QSOs by hour and band, countries, continents, CQ and ITU zones, WPX prefixes, distance, beam heading, callsign length and structure and your breaks and off time. You can edit calls or zones in the report and download a corrected Cabrillo. It works with Cabrillo from N1MM Logger+, DXLog and Win-Test, and you can compare the pattern with your own earlier logs. The contest list shows which of the 22 contests it supports.
Comparing years matters. If your corrections are always in the same hours, the cause is probably in the routine, such as the same rest plan or the same weak band. If they move from year to year, conditions or the schedule may have shifted.
What to change
When you know which hours are risky, the options are practical and mostly simple.
- Plan the rest. If the weakest hours are known, take the longest break shortly before them, as far as the rules allow. The rules for breaks differ, so see the article on off time and breaks. Operators in 48-hour contests also find the advice in the article on operator fatigue and breaks useful.
- Slow down a little. A small drop in speed that avoids several busted calls is better than a high rate with errors. The rate meter helps you to see the effect; see the article on the rate meter.
- Ask for repeats on principle in the weak hours. Make it a rule: any call that is not completely clear gets one repeat. It costs a few seconds, and the benefit lasts for the whole result.
- Do not rely on suggestions. A suggestion list is a help, not a witness. If what you heard and what the logger suggests are different, trust the repeat.
- Keep the station comfortable. Good light, a comfortable chair, a clear screen and water close by reduce the small errors that fatigue makes worse.
- Use the best operator for the worst hours. In a multi-operator station, schedule the most reliable listener for the hours when copying is most difficult, or rotate more often.
The night looks different by mode
The same fatigue shows up in different forms depending on the mode. In CW, a tired operator drops characters and confuses similar letters and numbers, and cut numbers can become a source of mistakes; see the article on cut numbers in CW. On SSB, the voice itself can be a problem: a hoarse operator is harder to understand, and the stations at the other end may hear a call differently from what was said. The article on SSB phonetics gives habits that help in both directions. On RTTY, the decoder keeps working while the operator tires, but accepting the decoded text without reading it becomes more likely in the small hours. In each case the principle is the same: when the quality of your own attention falls, increase the checks that do not depend on it, such as repeats and a short glance at the entry before you confirm it.
Keeping a short log of your own
A simple note kept during the contest, with the time and a few words each time you feel the quality dropping, is worth more than memory. After the contest, the notes explain the statistics: a period of low rate with a note “very tired, QRN” is clearly different from a period of low rate on a closed band. The same routine is useful in the week after the contest, and the article on the post-contest review routine shows how to include it.
Related reading
- Operator fatigue and breaks in 48-hour contests
- Hour-by-hour analysis of a contest log
- CW copying accuracy in contests
The bottom line
Errors at night are not a surprise; they are the predictable result of tired ears, weak signals and long hours. Find your own risky hours by comparing the QSOs you corrected with your hourly statistics, then change the plan: rest earlier, listen more carefully and repeat more often when the signals are poor. You will not remove every error, but you can move most of them out of the hours that cost you the most.
FAQ
Are logging errors really more common at night?
Many contesters report it, because fatigue, weak signals and noise coincide. Your own log shows whether it applies to you.
Can the statistics show me my errors by hour?
They show your rate, QSOs by hour and band and breaks. Combine them with the times of the QSOs you corrected to see the pattern.
Should I slow down at night?
Often a little, especially when signals are weak. A few seconds for a repeat can save a QSO and a multiplier.
Are dupes at night a problem?
Dupes are not errors, but several of them in a short period may show that attention is slipping.
What is the best way to prevent night errors?
Plan rest before the weakest hours, ask for repeats on principle and review the callsigns after the contest.
