RBN Analytics

Skimmer frequency accuracy

To be a good RBN citizen a skimmer should have a frequency accuracy of 2ppm or better.

To use the data below to improve the accuracy of your skimmer, multiply the current value of FreqCalibration in your skimmer software’s settings file with the suggested adjustment factor listed below.

The location of the settings files are:
CW Skimmer Server: %appdata%\Afreet\Products\SkimSrv\SkimSrv.ini
CW Skimmer: %appdata%\Afreet\Products\CwSkimmer\CwSkimmer.ini

The data listed here is based on archived RBN data from the previous day, 00:00 to 23:59 UTC. When making adjustments, this means that changes in calibration will not have full impact on the listed data until the second day after the change.

The deviation estimates listed below are based on spots on all active bands (40m and above) from the respective skimmer. If different hardware is used for different bands, the deviation number may thus not represent the actual deviation for a particular band.

The software used to calculate the tables below can be found here. It runs as a cron job in an Ubuntu container on my server and uploads to this WordPress site ten minutes after midnight UTC every night.

The calculation of deviation estimates is done in two steps. The first step uses a small number of highly accurate skimmers (called “anchors” in the code, typically GPSDO-controlled skimmers) as reference. The whole estimation process is then repeated one more time but using both the anchors as well as all skimmers determined to be the “good” as reference. The “good” skimmers are those with less than 0.15ppm average deviation from the anchors, producing more than 100 qualifying spots (the qualification criterion of spots are outlined below.)

Repeating the analysis with this this extended set of skimmers as frequency reference drastically increases the geographical coverage of the algorithm, in turn increasing the number of qualifying spots, thus leading to much more reliable deviation estimates for all skimmers. The skimmers used as reference skimmers in the second stage (i.e. both anchors and “good”) are marked with an asterisk in the table below.

When looking at the numbers, keep in mind that the deviations estimated by the algorithm is 100 to 1000 times smaller than the 100Hz resolution of RBN frequency data. The input data is thus extremely “noisy” which inevitably leads to statistical variations.

Due to propagation characteristics, operator behavior (e.g. small QSY), and just statistical variations, some skimmers selected as reference skimmers in the first stage may have more than 0.2ppm deviation in the second stage. This is not an error.

1246893 RBN spots between 2021-04-11 00:00 and 23:59 UTC.
181043 spots (14.5%) were from reference skimmers (*).
Average spot flow was 866 per minute from 181 active CW skimmers.

411090 spots from 177 skimmers qualified for analysis by meeting
the following criteria:
 * Mode of spot is CW.
 * Also spotted by a reference skimmer within 1000 spots.
 * Also spotted by a reference skimmer within 10s. 
 * SNR is 3dB or higher. 
 * Frequency is 7000kHz or higher. 
 * Frequency deviation from reference skimmer is 0.5kHz or less.
 * At least 5 spots from same skimmer in data set.

  Skimmer    [ppm]  Spots    Adjustment 
  -------------------------------------
  3B8CW       +0.1    501   1.000000095
  3D2AG       -0.7    193   0.999999262
  3V/KF5EYY   +0.5   2957   1.000000512
  5W1SA       +0.7    259   1.000000734
  9A1CIG      +3.1   1592   1.000003116
  9V1KB       +0.0    157   1.000000045
  9V1RM       -0.5    436   0.999999524
  AC0C-1*     -0.0   1581   0.999999962
  BA7KW       +3.1    675   1.000003118
  BA7QT       +0.0    378   1.000000000
  BD7JNA      +0.1    379   1.000000132
  BD7LMD      -1.4     56   0.999998600
  BD7MLA      +1.6   1336   1.000001561
  BD7NWR     +14.9     51   1.000014945
  BD8SZ       +0.6    154   1.000000632
  BG4GOV      -0.1    555   0.999999922
  BG8PA*      -0.0   1005   0.999999964
  BH4RRG      +3.8    502   1.000003824
  BH4RRG0     +1.3    450   1.000001315
  BH4RRG1     +2.1    240   1.000002107
  BH4XDZ      +0.5    105   1.000000543
  CT7ANO      -0.2   4069   0.999999772
  CX6VM*      -0.1   1162   0.999999912
  DD5XX       +0.3   3315   1.000000276
  DE1LON      +0.5   5408   1.000000549
  DF4XX       -0.5   3516   0.999999543
  DF5EG       -2.1    451   0.999997945
  DF7GB*      -0.0   6394   0.999999962
  DK0TE       +2.6   5052   1.000002598
  DK3UA       -0.5   1272   0.999999525
  DK9IP       +0.1   4914   1.000000134
  DL0LA       +1.4   5522   1.000001383
  DL0PF       +1.2   6489   1.000001174
  DL3DTH      +0.3   6413   1.000000286
  DL8LAS      -4.2   4203   0.999995754
  DL8TG       -1.2   4238   0.999998800
  DM6EE       -3.5   1941   0.999996491
  DM7EE       +0.6   4693   1.000000559
  DR4W        +4.4   6737   1.000004398
  E28AC       -6.8   1849   0.999993237
  EA1URA      +1.6   5562   1.000001595
  EA2NN*      -0.1    748   0.999999867
  EA5WU       -0.7   4481   0.999999328
  EA8BFK*     +0.0   4808   1.000000015
  ES5PC       +0.7   2906   1.000000725
  F4VSQ       +4.6   1070   1.000004646
  F5AHD       +0.3   1385   1.000000260
  F6IIT       -0.9   7419   0.999999057
  F8DGY       -0.5   6906   0.999999461
  G0TMX*      +0.1   1164   1.000000082
  G4HSO       -0.2   2010   0.999999769
  G4ZFE       +0.2   4525   1.000000182
  G5ROB       +0.5    206   1.000000518
  GI4DOH      +2.7   1574   1.000002670
  GM6DX       +1.0    698   1.000000970
  HA1VHF      -0.1   6065   0.999999891
  HA5PP       +2.0    298   1.000001962
  HA6PX       +5.7   2928   1.000005722
  HA7GN       -0.3   2759   0.999999687
  HA8TKS      +0.7   2011   1.000000715
  HB9BXE      +0.3    503   1.000000298
  HB9DCO      -0.3   3426   0.999999725
  HB9JCB      +1.9   5612   1.000001851
  HG8A        -1.9   5487   0.999998133
  IK3STG      -0.9   3437   0.999999094
  IK4VET-1    +0.5   7371   1.000000518
  IZ2CPS      -1.0   3633   0.999999024
  JA4ZRK      +0.3    260   1.000000291
  JG1DLY      -0.7    170   0.999999287
  JG1VGX      -1.6     77   0.999998412
  JH7CSU1     +3.8   1551   1.000003815
  JI1HFJ      -7.4    691   0.999992575
  JJ2VLY      -1.4   1293   0.999998631
  JQ1BVI      -0.1   1291   0.999999934
  JQ1YUF      +0.1   1311   1.000000083
  JR1BFZ/2    -0.4    352   0.999999605
  K1FC        -0.2     88   0.999999838
  K1TTT*      -0.1   1592   0.999999851
  K2DB*       +0.2   1193   1.000000190
  K2PO/7      +0.6   1543   1.000000574
  K3PA*       +0.1   2172   1.000000055
  K4BEN      -14.2    823   0.999985765
  K5TR        +0.8   2242   1.000000765
  K7EG        +1.0    764   1.000000975
  K7MJG*      +0.1    544   1.000000066
  K9IMM*      +0.0   2267   1.000000023
  K9LC        +0.4   2267   1.000000367
  K9TM-4      +0.7   2366   1.000000659
  KC0VKN      -0.4    252   0.999999558
  KC4YVA      +4.7    604   1.000004696
  KD2OGR*     -0.3    801   0.999999699
  KD7YZ       +0.3   2496   1.000000256
  KH6LC       -0.3    344   0.999999717
  KL7RA      +19.0      9   1.000019006
  KM3T*       +0.0   3993   1.000000035
  KM3T-1*     -0.1    630   0.999999932
  KM3T-2      +0.7   4531   1.000000682
  KO7SS       +1.4   2239   1.000001371
  KO7SS-7*    +0.2   1743   1.000000153
  KP2RUM*     -0.1   1733   0.999999871
  KQ8M        +7.2    611   1.000007195
  KU7T        -0.4   1682   0.999999613
  LZ3CB*      +0.0   5216   1.000000034
  LZ4AE*      -0.0   6494   0.999999954
  LZ4UX*      +0.0   4000   1.000000012
  MW0MUT      +0.4   6040   1.000000426
  N4TVC       +0.3   1902   1.000000296
  N4ZR/3      +0.2   2593   1.000000227
  N6TV        +0.3    877   1.000000263
  N6WIN-7     -0.6   1217   0.999999423
  N7TUG       -0.1    314   0.999999909
  NA0B        +0.2    115   1.000000248
  NC7J        +0.6   1344   1.000000600
  NN3RP       -0.9    500   0.999999149
  OE9GHV*     +0.0   7065   1.000000049
  OG73X       +1.4   1532   1.000001423
  OH6BG       -1.9    378   0.999998135
  OK2EW       -0.7  12472   0.999999316
  OL7M        +1.7   5062   1.000001677
  ON6ZQ       +1.0   4295   1.000001021
  PA0MBO      +0.3   1991   1.000000263
  PA3GRM      +0.2   1578   1.000000230
  PA5KT       -1.1   1040   0.999998904
  PJ2A        -2.0   2234   0.999997977
  R6YY        +1.3   5299   1.000001297
  RL3A-2      +1.9   2410   1.000001862
  RN4WA       -0.4   5699   0.999999618
  RU9CZD      +3.2   3302   1.000003233
  S50ARX      +0.6   1049   1.000000611
  S53M        -4.0      9   0.999996040
  SJ2W        +0.9   5174   1.000000928
  SM0TCZ      +2.2    871   1.000002233
  SM6FMB*     -0.1   4588   0.999999933
  SM7IUN*     +0.1   6114   1.000000132
  SP5SR       +0.6    570   1.000000575
  SV8RV       +3.1   4677   1.000003126
  SZ1A        -0.2   5074   0.999999820
  TF3Y        -0.5   3292   0.999999483
  TF4X        -1.9   8008   0.999998077
  UA4M        +5.1    333   1.000005096
  UA9LIF      +5.9    754   1.000005871
  UY2RA       +0.3   1950   1.000000321
  V51YJ       -1.7    163   0.999998252
  VE2WU*      +0.1   2082   1.000000062
  VE6AO       -1.4    530   0.999998602
  VE6WZ       +1.7   1680   1.000001651
  VE7AB       +1.1    180   1.000001148
  VE7CC*      -0.0   1596   0.999999991
  VK2GEL      +3.2     36   1.000003180
  VK4CT       -1.5   1510   0.999998487
  VK6ANC      -1.0    844   0.999999049
  VU3KAZ      +0.5    390   1.000000457
  VY0ERC      -1.0     14   0.999998982
  W1NT-2      -1.1   3533   0.999998931
  W1NT-6      -0.7   5142   0.999999332
  W2AXR       +0.6   2708   1.000000640
  W2NAF       +0.7    878   1.000000728
  W3LPL       +1.1   3104   1.000001085
  W3OA*       -0.1    165   0.999999914
  W3RGA       +0.3   2606   1.000000328
  W4AX        +3.6    477   1.000003646
  W4KAZ       -1.1   1685   0.999998862
  W6YX        +0.1   1190   1.000000079
  W7HR        +0.7    895   1.000000696
  W8WWV       +0.7   2548   1.000000698
  W9XG        +4.5   1074   1.000004491
  WA7LNW      -0.4   2178   0.999999554
  WA9VEE      +0.0      7   1.000000000
  WB6BEE*     -0.1   1991   0.999999892
  WC2L        +0.1    963   1.000000148
  WE9V        -0.6   2779   0.999999418
  WS3W        +0.5   2001   1.000000513
  WZ7I*       -0.1   4554   0.999999924
  YL2SW*      -0.1   5596   0.999999944
  ZL2BR      -13.6    164   0.999986448
  ZL4YL       +1.6   1611   1.000001579
  ZS6BNE      +1.5     58   1.000001473

Last updated 2021-04-12 00:10:43 UTC

Historical skimmer frequency accuracy

Below you will find historical accuracy data for the past five days. Do not be concerned over minor daily variations. Since RBN spots only have 100Hz frequency accuracy, the input data is very noisy. Even for a perfectly accurate skimmer, the typical RMS rounding error across all shortwave bands is around 3ppm. This means that for a skimmer with 1000 spots per day the statistical variation is up to 0.2ppm. For skimmers with less than 100 spots per day the statistical variation can be above 2ppm. The content of the table below is based on the historical content of the above table.

Skimmer      21-04-11  21-04-10  21-04-09  21-04-08  21-04-07
-------------------------------------------------------------
3B8CW          +0.1      +0.4      -0.0      -0.1      +0.9
3D2AG          -0.7      -0.7      +0.0      -1.3      +0.0
3V/KF5EYY      +0.5      +0.3      +0.3      +0.1      +0.4
5W1SA          +0.7                          +0.4      +0.7
9A1CIG         +3.1      +2.0      +1.5      +2.8      +1.6
9V1KB          +0.0      +0.1      +0.0                    
9V1RM          -0.5      -0.5      -0.4      +0.1      -1.0
AC0C-1         -0.0      -0.0      +0.1      -0.0      +0.0
BA7KW          +3.1      +2.4      +2.3      +2.1      +3.5
BA7PC                              +0.8      +0.9          
BA7QT          +0.0      +0.0      +0.0      +0.0      +1.5
BD7JNA         +0.1      +0.2     +13.0      -1.2      -4.6
BD7LMD         -1.4                                        
BD7MLA         +1.6      +1.3      +1.1      +1.4      +1.8
BD7NWR        +14.9                                        
BD8SZ          +0.6      +0.1      +0.0                    
BG2UKX                  +40.1                              
BG4GOV         -0.1      -0.4      -0.7      -0.3      -1.7
BG8PA          -0.0      +0.0      +0.1      +0.0      +0.1
BH1VCS                  +11.4                              
BH4RRG0        +1.3                                        
BH4RRG1        +2.1                                        
BH4RRG         +3.8      -0.8      -2.5      -4.7      -6.8
BH4XDZ         +0.5      +0.3                              
BY1CY                              +0.0                +0.0
CT7ANO         -0.2      +0.2      +0.1      -0.2      -0.0
CX6VM          -0.1      -0.1      +0.0      -0.0      -0.3
DD5XX          +0.3      +0.2      +0.4      +0.2      +0.4
DE1LON         +0.5      +0.2      -0.1      +0.0      +0.6
DF4XX          -0.5      -0.2      +0.0      +0.2      -0.2
DF5EG          -2.1      -2.1                              
DF7GB          -0.0      -0.0      +0.1      -0.1      +0.0
DK0TE          +2.6      +2.2      +1.8      +1.4      +1.5
DK3UA          -0.5      -0.4      -0.2      -0.4      -0.2
DK9IP          +0.1      +0.0      +0.1      +0.0      +0.1
DL0LA          +1.4      +1.1      +0.7      +0.7      +1.0
DL0PF          +1.2      +0.8      +0.7      +0.5      +0.7
DL3DTH         +0.3      +0.1      +0.2      +0.1      +0.1
DL8LAS         -4.2      -4.3      -4.2      -3.6      -3.5
DL8TG          -1.2      -1.1      -0.8      -0.9      -1.0
DM6EE          -3.5      -3.5      -2.0      -3.3      -2.8
DM7EE          +0.6      +0.4      +0.4      +0.2      +0.3
DO4DXA                             -0.4                    
DR4W           +4.4      +3.5      +2.4      +1.6      +1.8
E28AC          -6.8      -8.7      -8.8      -8.7      -7.6
EA1URA         +1.6      +1.3      +1.3      +1.2      +1.4
EA2NN          -0.1      +0.0                              
EA5WU          -0.7      -0.7      -0.7      -0.8      -0.5
EA8BFK         +0.0      -0.0      -0.1      -0.1      +0.0
ES3V                                         -1.8      -1.7
ES5PC          +0.7      +0.9      +0.0      +0.2      +0.4
ET3AA                              +0.4      +0.3      +0.8
F4VSQ          +4.6      +2.8      +8.0      +9.5      +4.9
F5AHD          +0.3      +0.2                -0.7      -1.2
F6IIT          -0.9      -0.8      -0.6      -0.8      -0.9
F8DGY          -0.5      -1.1      -3.5      +0.1      -1.6
G0TMX          +0.1                                        
G4AON                              +1.0      +0.9      +1.1
G4HSO          -0.2      -0.6      -1.1      -0.6      +0.0
G4ZFE          +0.2      +0.1      +0.2      +0.1      +0.1
G5ROB          +0.5      +0.7      +1.2      +0.0          
GI4DOH         +2.7      +0.5      +0.2      +0.1      +0.0
GM6DX          +1.0      +0.6      +0.8      +0.7      +0.4
HA1VHF         -0.1      -0.2      -0.5      -0.6      -0.4
HA5PP          +2.0                                        
HA6PX          +5.7      +3.9      +2.0      +1.3      +2.5
HA7GN          -0.3      -0.6      -0.7      -0.9      -0.8
HA8TKS         +0.7      +0.4      +0.3      +0.1      +0.3
HB9BXE         +0.3      +0.5      +0.7      +0.3      +0.6
HB9DCO         -0.3      -0.1      -0.1      +0.0      +0.1
HB9JCB         +1.9      +1.6      +1.2      +1.2      +1.3
HG8A           -1.9      -1.2      -1.0      -0.7      -0.7
IK3STG         -0.9      -1.0      -1.0      -1.2      -1.2
IK4VET-1       +0.5      +0.6      +0.7      +0.3      +0.1
IZ2CPS         -1.0      -0.9      -1.0      -0.9      -0.9
JA4ZRK         +0.3      -0.2      +0.0      +0.6      -0.4
JG1DLY         -0.7      +0.2                              
JG1VGX         -1.6      -1.3                              
JH7CSU1        +3.8      +3.1      +3.0      +2.0      +3.5
JI1HFJ         -7.4      -8.8      -4.8                    
JJ2VLY         -1.4      -1.4      -1.6      -1.6      -1.0
JQ1BVI         -0.1      -0.2      -0.3      +0.2      +0.6
JQ1YUF         +0.1      -0.9      -1.4      -1.1      -1.9
JR1BFZ/2       -0.4      -0.3      -0.1      +0.3      -1.0
K1FC           -0.2      -0.5      +0.0                -3.3
K1TTT          -0.1      -0.2      -0.4      -0.3      -0.1
K2DB           +0.2      -0.1      +0.0      -1.8      -2.1
K2PO/7         +0.6      +0.4      +0.5      +0.4      +0.6
K3PA           +0.1      -0.1      +0.0      +0.2      +0.0
K4BEN         -14.2     -14.1     -14.8                    
K5TR           +0.8      +0.7      +1.0      +1.0      +0.8
K7EG           +1.0      +0.7      +0.9      +1.2      +1.5
K7MJG          +0.1      +0.1      +0.2      +0.3      +0.2
K9IMM          +0.0      -0.1      -0.1      +0.0      +0.2
K9LC           +0.4      +0.2      +0.3      +0.1      +0.5
K9TM-4         +0.7      +0.3      +0.3      +0.5      +0.7
KC0VKN         -0.4      -1.0      -0.3      -0.2      +0.4
KC4YVA         +4.7      +4.9      +4.0      +3.5      +5.3
KD2OGR         -0.3      -0.7      -0.2      -0.2      -0.2
KD7YZ          +0.3      +0.3      +0.1      +0.1      +0.2
KH6LC          -0.3      +0.1      +0.0      +0.0      -0.5
KI4PAD                                       +0.0          
KL7RA         +19.0      +2.9                              
KM3T           +0.0      -0.1      -0.0      -0.0      +0.0
KM3T-1         -0.1      +0.1      +0.1      +0.4      +0.1
KM3T-2         +0.7      +0.6      +0.5      +0.6      +0.4
KO7SS          +1.4      +1.1      +1.3      +1.3      +1.0
KO7SS-7        +0.2      +0.0      +0.3      +0.3      -0.0
KP2RUM         -0.1      -0.1      -0.3      -0.1      -0.1
KQ8M           +7.2      +8.0      +7.0      +9.1      +7.6
KU7T           -0.4      -0.5      -0.3      -0.3      -0.3
LA6TPA                                       +0.1      +0.5
LZ3CB          +0.0      +0.0      +0.1      -0.0      -0.1
LZ4AE          -0.0      -0.3      -0.1      -0.2      -0.1
LZ4UX          +0.0      -0.0      +0.0      +0.0      +0.1
MW0MUT         +0.4      +0.5      +0.5      +0.5      +0.2
N0OI                               +4.7      +3.3      +4.3
N4TVC          +0.3      +0.1      +0.5      +0.4      +0.3
N4ZR/3         +0.2      +0.1      -0.2      -0.1      -0.0
N6TV           +0.3      +0.1      +0.4      +0.5      +0.3
N6WIN-7        -0.6      -0.8      -0.3      -0.7      -0.4
N7TUG          -0.1      +0.4      +1.0      -0.0      +1.1
NA0B           +0.2      +0.4      +0.0      +0.0      +0.3
NC7J           +0.6      +0.5                              
NN3RP          -0.9      -1.0      -0.2      -1.3      -1.4
OE6ADD                             +1.1      +0.8      +1.1
OE9GHV         +0.0      -0.1      +0.1      -0.0      -0.1
OG73X          +1.4      +1.1                              
OH6BG          -1.9      -1.8      -1.8                    
OK2EW          -0.7      -0.7      -0.6      -0.7      -0.6
OL7M           +1.7      +0.2      -0.3      -0.4      -0.1
ON6ZQ          +1.0      +1.0      +0.7      +0.6      +1.1
PA0MBO         +0.3      +0.3      +0.2      +0.0      +0.2
PA3GRM         +0.2      +0.1                              
PA5KT          -1.1      -1.6                          +0.0
PJ2A           -2.0      -1.7      -1.2      -1.5      -1.6
R6YY           +1.3      +1.1      +1.1      +0.8      +1.0
RK3TD                                        +0.0      +0.1
RL3A-2         +1.9      +0.9      +0.5      +0.2      +0.5
RN4WA          -0.4      -0.3      -0.4      -0.5      -0.2
RU9CZD         +3.2      +2.4      +2.2      +1.6      +2.0
S50ARX         +0.6      +1.0      +0.3      +0.4      -0.2
S53M           -4.0                                        
SJ2W           +0.9      +0.7      +0.6      +0.6      +0.8
SM0TCZ         +2.2      +1.7      +1.6      +1.3      +1.6
SM6FMB         -0.1      +0.0      +0.1      +0.0      -0.0
SM7IUN         +0.1      -0.0      +0.1      -0.0      +0.2
SP5SR          +0.6      +0.5      +0.1      +0.2      +0.8
SV8RV          +3.1      +2.9      +2.6      +2.6      +2.9
SZ1A           -0.2      -0.5      -0.6      -0.5      -0.2
TF3Y           -0.5      -0.3      -0.4      -0.5      -0.3
TF4X           -1.9      -1.9      -1.7      -2.1      -1.8
UA4M           +5.1      +3.9      +3.9      +3.9      +4.1
UA9LIF         +5.9      +5.4                              
UR6EA                                                  -0.8
UY2RA          +0.3      +0.3      +0.4      +0.3      +0.3
V51YJ          -1.7      -3.3      -2.8      -2.8      -2.1
VE2WU          +0.1      -0.2      -0.2      -0.3      -0.1
VE6AO          -1.4      -0.8      -1.0      -0.4      -1.3
VE6WZ          +1.7      +1.5      +1.4      +1.7      +1.7
VE7AB          +1.1      +0.2      +1.5      +1.8      +2.9
VE7CC          -0.0      +0.1      +0.0      +0.2      +0.0
VK2GEL         +3.2      +5.3      +1.2      +3.0      +0.0
VK3RASA                 -12.0                -6.7      -9.4
VK4CT          -1.5      -0.8      -0.9      -0.5      -1.0
VK6ANC         -1.0      -0.5      -1.3      -0.1      -1.1
VU3KAZ         +0.5      -0.4                +0.0      -1.1
VY0ERC         -1.0      -1.4      -4.1                    
W1NT-2         -1.1      -1.1      -0.9      -0.9      -1.1
W1NT-6         -0.7      -0.7      -0.6      -0.7      -0.8
W2AXR          +0.6      +0.6                              
W2NAF          +0.7                                        
W3LPL          +1.1      +0.9      +0.9      +0.9      +1.2
W3OA           -0.1                          +0.0          
W3RGA          +0.3      +0.2      +0.2      +0.5      +0.2
W3UA                               +2.8                    
W4AX           +3.6      +3.6      +3.7      +2.7      +4.1
W4KAZ          -1.1      -1.2      -0.9      -1.2      -1.4
W6YX           +0.1      +0.1      +0.1      +0.2      +0.3
W7HR           +0.7      +0.7      +0.6      +1.3      +1.0
W8WWV          +0.7      +0.7      +0.7      +0.6      +0.8
W9XG           +4.5      +4.1      +4.6      +4.8      +4.5
WA7LNW         -0.4      -0.5      -0.3      -0.6      -0.5
WA9VEE         +0.0      +0.0      -0.6      +0.0      -1.0
WB6BEE         -0.1      -0.1      -0.1      +0.1      -0.0
WC2L           +0.1      +0.1      -0.2      -0.0      -0.0
WE9V           -0.6      -0.8                          -0.3
WS3W           +0.5      +0.1      +0.3      -0.1      +0.7
WZ7I           -0.1      -0.1      +0.1      -0.0      -0.0
YL2SW          -0.1      +6.4     +12.7                    
ZL2BR         -13.6     -14.1     -14.9     -14.7     -13.2
ZL3X                     +1.6                          +5.4
ZL4YL          +1.6      +1.4      +0.9      +1.1      +1.1
ZS6BNE         +1.5      +2.3                              

Last updated 2021-04-12 00:11:04 UTC

Activity statistics

Summary of unique calls spotted and active skimmers per band and continent.

RBN activity between 2021-04-11 00:00 and 23:59 UTC.
1246893 spots with 13775 unique callsigns from 189 active skimmers.

        Unique callsigns spotted per continent and band
---------------------------------------------------------------
    160m  80m  60m  40m  30m  20m  17m  15m  12m  10m   6m
AF     7   33    0  104   10   74   16   13    2    7    0  198
AS    59  320    2 1014  136  813   99  309   13  101   37 1968
EU   386 2349  165 3230 1166 2807  324  352   10   57   25 7266
NA   143  842   31 2027  430 1667  171  198   16   82   10 3773
OC    10   30    0  155   30  133   10   87    4   26    0  348
SA     1   15    0   74   16   90   32   51    5   20    0  222
     606 3589  198 6604 1788 5584  652 1010   50  293   72

        Active skimmers per continent and band
---------------------------------------------------------------
    160m  80m  60m  40m  30m  20m  17m  15m  12m  10m   6m
AF     3    3    1    5    4    4    4    4    3    4    0    5
AS    17   22    0   26   17   28   14   28   12   20    6   29
EU    61   68   21   73   57   73   43   54    5   21    6   80
NA    42   51   14   59   44   54   36   47    9   24    6   62
OC     5    7    0   10    7   10    6    8    2    4    0   10
SA     2    2    0    2    2    2    2    2    1    1    0    3
     130  153   36  175  131  171  105  143   32   74   18

Last updated 2021-04-12 00:12:53 UTC