Errors in logs of the RUSSIAN DX CONTEST 2003 averaged 6.5% of the total number of QSOs. This is about the same as the last three years. However the ratio of the nature of the errors has changed:
  • the number of not in log QSOs (NIL) has decreased to .5% (.7% in 2002)
  • the number of wrong exchange (received) has decreased to 1.2% (1.4% in 2002)
  • the number of incorrectly received callsigns has increased to 1.85% (1.6% in 2002)

The other errors are: incorrect time, band or mode - .1% of the total number of QSOs (systematic errors not included).

The UBN files, containing list of errors made, sent out in 2002 contributed to a noticeable decrease in errors in the logs of traditional contest participants.

The most frequent errors of callsigns and exchanges received could be divided in several distinctive groups. Nature of error, number of such errors in logs of all participants and most character examples are listed below.

    1. Errors in receiving prefixes
    These occur in prefixes of countries where several prefixes are being used, and "similar" prefixes belonging to different countries. The frequency of such errors is practically same for SSB and CW.
  • Errors in the first character of a prefix: RA-UA, K-N-W, G-M and similar (for instance, an error in first symbol Of Russian Stations R-U and vise versa was registered 658 times). There are 1128 errors of this kind altogether.
    Here are few examples:
      U-R    272    UA1ANA - RA1ANA
      R-U    386    RA3RIU - UA3RIU
      E-U     38    EW1GA - UW1GA
      N-K           N2OW - K2OW
      J-O           JA3YPL - OA3YPL
      M-G           M0CSU - G0CSU
  • Errors in the second symbol of a prefix: IK-IS-IZ, JA-JH-JK, OK-OM, RA-RK-RZ-RU-RX-RN-RV, SP-SQ, UN-UR-US, UT-UY - Totaled 3340 errors. Examples:
      Z-K     42    RZ9MYL - RK9MYL, IZ8DBJ - IK8DBJ
      K-Z     38    RK4HWW - RZ4HWW
      A-U     90    RA4AO - RU4AO
      U-A     48    RU0LL - RA0LL
      W-A     74    RW9OS - RA9OS
      N-R     34    UN7EED - UR7EED
      S-T           US7IGF - UT7IGF
      U-T           YU1EQ - YT1EQ
  • Similar errors in 2 symbols (for instance, MM0-GW0) - 212 errors.
  • Missed, or, on the contrary, added 2nd symbol of a prefix (For instance, I0IGV instead of IS0IGV) 576 errors.
  • Transposed symbols in "look alike" prefixes RU-UR, LY-YL, YU-UY 209 total, but part of them might be considered as typos. Examples:
      Y-L     42    YL6W - LY6W
      L-Y     19    LY1YK - YL1YK

2. Hearing errors, which are different on CW and SSB
On CW the most frequent errors are in receiving symbols which sound "similar" H-S (696 total, 527 participants Received "S" instead of "H" and only 169 "H" instead of "S". Same errors occurred in receiving 2-letter Oblasts identifiers, but the frequency of those were lower because of the use of adapted RDXC software.

Examples of CW errors:

       H-S    527    RA4HT - RA4ST, HM - SM
       S-H    169    ON7SA - ON7HA, ST  HT

       B-D    148    ON4AEB - ON4AED, CB - CD
       D-B    136    UA9CDC - UA9CBC, AD  AB

       S-I    129    RU9SL - RU9IL, SV - IV
       I-S     68    EI4DW - ES4DW, IR  SR

       U-V    112    SU9NC - SV9NC, UD - VD
       V-U    108    RV1AT - RU1AT, IV  IU

       I-E     52    RA4AI - RA4AE, KI - KE
       E-I     28    PI4DEC - PI4DIC, PE  PI

       X-K     40    RX3RZ - RK3RZ,
       K-X     33    OM3EK - OM3EX, KR  XR

       L-R     40    HA0LP - HA0RP, UL - UR
       R-L     25    UA0QBR - UA0QBL

       M-N     29    PA0MIR - PA0NIR, HM - HN
       N-M     25    SN7Q - SM7Q

       Z-G     61    RZ3AZ - RZ3AG
       A-T     46    RK3AWA - RK3AWT, BA - BT
       W-M     38    N2OW - N2OM
       C-K     32    RA1AC - RA1AK, CB - KB
       D-N     31    OH5DX - OH5NX
       5-H    223    5B4AGC - HB4AGC, S59AA - SH9AA
       H-5     25    UX3HA - UX35A
       B-6     24    BW4/UA3VCS - 6W4/UA3VCS

CW errors in numerals reception in call signs and exchange numbers were distributed quite evenly. The majority of errors were with the following numerals:

       5-4    408    UN4L - UN5L, 154 - 144
       4-5    299    UR5E - UR4E, 014 - 015

The majority of errors on CW occurred while receiving the last numeral of the number of the QSO.

Excessive number of symbols in call sign reception on CW 291, at the end of call sign 251. The majority of errors of this kind an extra character "T" (55 occurances). Special attention should be paid for CW errors which occur because of sending a callsign and next code combination without an interval.

        callsign + "TEST"  55     RK9AY - RK9AYT, EA6UN - EA6UNT
        callsign + "BK"    54     T92D - T92DB

    Missed symbols on CW (not counting call signs, having / as a part of callsign):
  • missed symbols in the middle of a call sign 227.
  • most frequently missed characters are: "E" - 44, "I" - 24.
  • there are no missing letters "O" and "W" at all.
  • missed symbols at the end of a call sign 672.
  • most frequent: "T" - 66, "K" - 32, "C" - 31. It should be taken into consideration that only few callsigns end with "K". Most rarely missed symbols "F"- 3, "Y" 1.

Missed numerals in exchange numbers 232. Mostly its a last numeral in a 4 digit exchange. Back in 2002 there were 1.5 times more errors. Looks like the participants became used to the fact, that exchanges often exceed 3 digit numbers.

3. Typical errors on SSB are linked to accustomed interpretation of English phonetics by different participants, particularity the pronunciation of their callsigns by different participants, DVP performance. For instance, in many countries Victor is associated with letter W, Canada with K, Easy with I.

Participants should pay attention to these symbols. There are significantly less errors in reception of oblasts identifiers because of the contest software. Besides the alternate identifiers contributed to avoid errors (JA=YA, JN=YN, etc).

       V-W    342    RV0AU - RW0AU, HA8JV - HA8JW, VL - WL
       W-V    108    RK6HWR - RK6HVR, EW7KR - EV7KR

       X-Z     85    RZ1CXO - RZ1CZO, LX1NO - LZ1NO

       G-J     75    RG4A - RJ4A, 9A2GA - 9A2JA
       J-G     45    RA9MJ - RA9MG, HA8JV - HA8GV

       Y-J     56    UA9AYA - UA9AJA, LY1YK - LJ1JK
       J-Y     25    RK9JWV - RK9YWV , IZ8DBJ - IZ8DBY

       C-K     51    RA9CO - RA9KO, YL7C - YL7K
       K-C     13    RA1QKB - RA1QCB, LZ1KSC - LZ1CSC

       O-A     40    RK9CZO - RK9CZA, H2O - H2A
       A-O     21    RU6FA - RU6FO, LA6HJA - LA6HJO

       M-N     35    UA9AM - UA9AN, LY3UM - LY3UN
       N-M     13    UA9HN - UA9HM, YL1XN - YL1XM

       E-I     38    RA3EA - RA3IA, PI4DEC - PI4DIC
       0-Z     39    I0ZQB - IZ0QB

Here are the most frequent errors in reception of numerals in call signs and exchange numbers n SSB. According to the frequency of errors on SSB the first numeral in the exchange is most vulnerable.

       2-3    135    RN2FB - RN3FB, DL2JRM - DL3JRM, 231 -331
       3-2    124    RA3AJ - RA2AJ, LY3BH - LY2BH, 063  062

       4-2    110    9A4KA - 9A2KA, UU4JWF - UU2JWF, 947 - 927
       8-9    102    IZ8DBJ - IZ9DBJ, US8IM - US9IM, 681 - 691
       4-3     87    RG4A - RG3A, YO4KBJ - YO3KBJ, 405 - 305
       9-8     59    HG9M - HG8M, RA9FLW - RA8FLW, 1349 - 1348
       1-9     52    YT1BB - YT9BB, 019 - 090
       9-0     46    DH9SB - DH0SB, RZ9UGN - RZ0UGN

Excessive symbols on SSB: in the middle of callsign - 29, in the end of callsign 119. None of the symbols prevail. Missed symbols in callsigns on SSB: in the middle of callsign-97, at the end 210. The letter A was the one to disappear -23 times. The least frequent to disappear "H" and "S" twice each only.

4. "Keypad" Errors
The next group of errors are the typos and graphic errors of those who had handwritten logs or those who entered the log into a computer after the contest was over. Unfortunately its extremely difficult to qualify the nature of these errors, such as transposition of symbols in a call sign, errors in absolutely different Symbols.

For instance, symbols "T" and "Y" could be transposed because of similarity in handwritten logs or because they are adjacent on a keyboard. Very often errors in reception of numerals could be explained because the appropriate keys are adjacent on a keyboard.

Transposed symbols 579. The occurrence is as more often as the key is closer to the center of a keyboard.

       H-    41     IK2HKT - IK2KHT, SP7LHX - SP7HLX, HM - MH
       J-    34     SP9LJD - SP9JLD, UA9MJW - UA9MWJ
       K-    34     SP8KEA - SP8EKA, I4MKW - I4KMW, KN - NK
       G-    31     F5HGT - F5GHT
       F-    30     UA9AFM - UA9AMF
       T-    27     IK2HKT - IK2HTK
       L-    24     UA9LCY - UA9CLY, UA9CLB - UA9CBL, KL - LK
       D-    23     SP9KDA - SP9DKA, DL9HD - DL9DH

In received exchanges the adjacent numerals were transposed most often:

       5-6   51     756 - 765
       6-7   39     076 - 067
       7-8   37     1871 - 1781

The number of typos and graphic errors increased at night time (local for each participant). It should be taken into consideration that handwritten logs, as a rule, are being written in evenings or nights.

    5. Errors in receiving fractal callsigns:
  • absence of a fractal part (RU3DX/3 - RU3DX, W2/UR5DEM - UR5DEM) - 219 errors
  • incorrectly received fractal part (MM0DFV/P - MM0DFV/M, RV6LGY/9 - RV6LGY/1) - 106 errors
  • missing symbol in fractal part (BW4/UA3VCS - BW3/UA3VCs, YU8/9X0A - YU/9X0A) - 79 errors
  • transposition of a fractal part (ZA/UT7DW - UT7DW/ZA, EA6/DL6KAC - DL6KAC/EA6) - 41 errors
  • more complex errors (HL1/WX8C - HL1GWX/8C, RN4ABJ/6 - RN6/RN4ABJ) - 52 errors

Considering that in addition to above mentioned errors, traditional errors can be added, but those participants can be considered High Risk Group. Nevertheless the constant number of different DXpeditions participating in RDXC is very welcome.

6. Errors in receiving of the Russian Oblasts Identifiers
Errors in receiving of the Russian Oblasts Identifiers by participants who were not familiar with the rules of the contest, or international system of callsigns, should form a separate group. In this case an Oblast Identifier was interpreted by them as number of QSO, for instance:

       VO - 040
       NV - 094
       TV - 004
       TB - 006
       NN - 099
       TA - 001
       SV - 054
       TN - 009
       BA - 061
       HA - 051

These errors are very difficult to systemize, and the total quantity of such is 71.

7. In-time error distribution during the Contest
In 2003 in-time error distribution smoothed out noticeably and did not have any splashes neither at the beginning nor at the end of the 24-hour period, as it happened in previous years.

Within the first hour of the test the number of errors were averaging 11%, regardless of a rate within the same period. Mostly those were errors in callsigns reception and not in log. Exchange numbers were being received correctly. If the participant began working not from the beginning of the test he did not have such an error growth.

By the 4th hour of the test the average percentage of errors decreased down to 4% and remained at the same level up to 02 UTC. The ratio among all kinds of errors was pretty much equal to average during the entire contest. A second splash of errors could be seen in logs of those who took lengthy time-off. This continued up to 1 hour after resuming operation. The errors reached up to 14%, those were wrong callsign and exchange reception. If a participant operated without time-off, the percentage of errors grew noticeably at 05 hours participants local time and often exceeded 10-15%. This splash was the longest one and continued from 1 to 3 hours. The same was true for MOST, although the operators could change. At this period for some reason only exchange numbers were incorrectly received, everything was OK with reception of call signs. During the last hour of the test the percentage of errors had increased again. Incorrect reception of exchange numbers, including identifiers of Russian Oblasts prevailed all. The Number of NILs also increased.

8. Average percentage of errors in logs of participants of RDXC 2003

Wrong callsign received
Wrong exchange received
Not in LOG
Number of errors on CW
% of errors on CW
Number of errors on SSB
% of errors on SSB
Total errors
Total % of errors

We would like participants to pay attention to the fact that the total number of CW errors seemed to be larger than that of SSB. The fact should be considered that in RDXC-2003 more than 59.7% of QSOs were made on CW, the remaining 40.3% - on SSB. The following is the ratio of errors to all checked QSOs percentage wise for each mode and total.

Mismatches of time of QSO, Mode (only for MIXED Group) and Band (only in multi-band Groups) constitute total of .12% for all logs.

    9. Errors band distribution
    Regardless of Mode and nature of errors they are distributed as follows:
  • 1.8 MHz - 26% (majority errors in call signs - 17% and NILs - 7%)
  • 3.5 MHz - 19% (nature of errors is even)
  • 7 MHz - 15% (nature of errors is even)
  • 14 MHz - 12% (nature of errors is even)
  • 21 MHz - 7% (majority NILs only - 5% from 7%)
  • 28 MHz - 21% (majority incorrectly received exchange numbers - 8% and NILs - 11%. Looks like quick propagation change on this band was the contributing factor.)

The organizers of the Russian DX contest hope that these statistics will help the participants to improve their results in this Contest. We wish everybody success and good luck in RDXC-2004! 73!

The analysis was prepared by RW1AC and UA1AAF