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 below is based on archived RBN data from the previous day, 00:00 to 23:59 UTC. This means that when making adjustments, 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.
A link to the software used to produce the tables can be found at the bottom of this page. It runs as a cron job in an Ubuntu container on my Synology server and uploads to this WordPress website shortly after midnight UTC every night.
The deviation estimation 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 references drastically increases the geographical coverage of the analysis thereby increasing the number of qualifying spots which means a 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. This is also the reason for not including spots under a certain frequency. They will just skew the statistics and cause underestimation of the frequency error.
Due to propagation characteristics, operator behavior (e.g. small QSY), and just statistical variations due to the 100Hz rounding, 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.
If you do not see your skimmer in the list below in spite of it successfully feeding spots to RBN the most likely reason is that it is off in frequency. The analytics discards all spots from skimmers having more than 0.5kHz frequency error.
1744324 RBN spots between 2023-02-05 00:00 and 23:59 UTC. 372054 spots (21.3%) were from reference skimmers (*). Average spot flow was 1211 per minute from 192 active CW skimmers. 837151 spots from 190 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* +0.0 634 1.000000012 3D2AG -0.2 546 0.999999760 5W1SA +1.3 444 1.000001324 7N4XCV +2.0 89 1.000001996 9M2CNC -0.3 361 0.999999717 AA4VV* +0.0 8123 1.000000009 AC0C-1 -0.1 8132 0.999999888 BA6KC +2.6 410 1.000002582 BD4QJP +0.8 52 1.000000787 BD7DT +0.3 1559 1.000000262 BD7JNA -0.6 100 0.999999358 BG4GOV +0.1 190 1.000000134 BG4GOV3 +4.7 28 1.000004731 BG4WOM -6.1 685 0.999993925 BG8FZU -0.9 1331 0.999999123 BH3BBJ +0.2 831 1.000000174 BH4DEG +3.3 167 1.000003280 BH4RRG +0.3 217 1.000000319 BH4RRG0 +2.0 559 1.000002028 BH4XDZ +0.5 279 1.000000504 BH4XDZ-1 +1.0 272 1.000000960 BI4MPH +8.9 12 1.000008898 BI4RFP-1 +1.3 421 1.000001302 CX6VM -1.8 1648 0.999998197 DC8YZ* +0.0 12107 1.000000039 DD5XX* -0.0 6277 0.999999993 DE1LON -0.9 9893 0.999999064 DE2SAX -0.7 2185 0.999999348 DF2CK* -0.1 13721 0.999999927 DF7GB* +0.0 11681 1.000000002 DG6FL -28.7 46 0.999971321 DK0TE +16.7 8396 1.000016676 DK9IP -0.2 6950 0.999999842 DL0LA* -0.0 6076 0.999999967 DL0PF +1.2 8785 1.000001204 DL1HWS +0.3 9887 1.000000288 DL8LAS +1.2 7001 1.000001180 DL8TG* -0.1 9916 0.999999934 DL9GTB -0.7 8411 0.999999285 DM5GG +0.3 10685 1.000000298 DM6EE* +0.1 5019 1.000000058 DO4DXA* -0.1 6100 0.999999890 DP7D +0.0 13 1.000000000 EA1DAV -0.8 11261 0.999999237 EA1RX -6.2 299 0.999993781 EA1URA* +0.1 8230 1.000000132 EA2CW -0.3 1992 0.999999717 EA2RCF-4* +0.0 7177 1.000000041 EA5WU -0.7 10256 0.999999293 EA8/DF4UE -0.5 15217 0.999999517 ES2RR -1.4 9220 0.999998626 EY8ZE -1.2 3613 0.999998759 F4VSQ +3.8 428 1.000003760 F6IIT -1.4 4973 0.999998553 F8DGY* +0.0 2960 1.000000014 G0KTN +0.3 9236 1.000000276 G0TAI -0.4 922 0.999999552 G3XBI +0.4 2771 1.000000399 G3YPP +0.1 1141 1.000000150 G4HSO -3.0 10593 0.999996957 G4ZFE -1.3 10163 0.999998735 GI4DOH* +0.0 5620 1.000000035 HA1VHF +0.6 8531 1.000000632 HA8TKS +0.2 7089 1.000000163 HB9BXE +0.4 5957 1.000000405 HB9CAT +4.7 2466 1.000004709 HB9DCO +0.5 8777 1.000000491 HB9RB -7.2 487 0.999992800 HG0Y -0.4 1617 0.999999572 HG5FMV +0.3 682 1.000000288 HG8A -0.4 8841 0.999999583 HS/F8UKP +0.1 319 1.000000073 IK3STG +4.5 3399 1.000004534 IK4VET +0.3 10068 1.000000282 JA4ZRK -0.7 62 0.999999318 JG1DLY -0.5 250 0.999999515 JH4UTP +0.0 97 1.000000000 JH7CSU1 +4.6 480 1.000004567 JI1HFJ -1.8 329 0.999998243 JJ2VLY -2.6 139 0.999997410 JN1ILK -0.6 2256 0.999999412 K1TTT -0.8 4776 0.999999226 K2PO/7 +0.7 3272 1.000000662 K3LR +2.5 5684 1.000002546 K3PA-1 +0.4 5545 1.000000398 K4PP +0.2 4688 1.000000185 K5TR +0.9 5315 1.000000927 K6FOD* +0.1 3674 1.000000090 K7EG +1.7 4629 1.000001662 K7EK -0.2 1879 0.999999838 K7MJG -8.7 2662 0.999991281 K9IMM* -0.0 5378 0.999999964 K9LC* -0.0 6136 0.999999976 KC4YVA +5.5 3098 1.000005535 KD2OGR +0.2 4502 1.000000155 KH6LC* -0.1 1754 0.999999863 KM3T* -0.0 8739 0.999999987 KM3T-2 -0.8 8209 0.999999153 KM3T-3 -0.7 9262 0.999999340 KV4TT +0.2 6033 1.000000208 LZ3CB* +0.0 4198 1.000000024 LZ4AE +3.2 9268 1.000003190 LZ4UX* +0.0 7066 1.000000011 LZ5DI* +0.0 2075 1.000000033 LZ7AA +0.4 8036 1.000000420 M0WTL -0.9 265 0.999999140 MM0ZBH -0.3 7746 0.999999661 MM3NDH* -0.0 6177 0.999999976 MW0MUT +1.0 9364 1.000001024 N4RLI -1.2 3555 0.999998824 N4ZR -1.0 180 0.999998957 N6TV* +0.1 1942 1.000000148 N7TUG +8.8 2240 1.000008800 NA0B* -0.1 1104 0.999999916 NC7J +0.7 5741 1.000000720 ND7K* -0.1 6736 0.999999867 NH6HI +5.3 28 1.000005313 NN3RP -0.2 4003 0.999999763 NR4U +0.2 3656 1.000000156 OE9GHV* +0.0 10934 1.000000025 OG66X -1.3 164 0.999998712 OH4KA -1.4 5693 0.999998634 OH6BG +0.6 6221 1.000000636 OK1FCJ* +0.1 7886 1.000000087 OK1HRA -4.0 4048 0.999996035 OK4QRO* +0.0 6281 1.000000045 OL9A +1.9 6060 1.000001910 ON3URE +1.9 7618 1.000001872 ON6ZQ -0.7 1495 0.999999264 OZ4ADX +0.3 708 1.000000282 PA0MBO +0.2 2684 1.000000226 PD2RPS +14.2 4316 1.000014155 PJ2A -0.5 3351 0.999999542 R6YY* +0.1 8257 1.000000084 R9IR* -0.2 760 0.999999824 RK3TD* +0.1 7619 1.000000079 RN4WA* -0.1 6856 0.999999899 RU9CZD -0.3 4645 0.999999670 S50C-1 +3.8 58 1.000003762 S50U +1.8 1949 1.000001825 S53A +0.8 11315 1.000000752 S53WW -3.3 9729 0.999996734 SE5E +0.3 8954 1.000000294 SM7IUN +0.2 8354 1.000000185 SV8RV +0.7 4943 1.000000671 TF3Y +1.4 7976 1.000001436 TF4M -1.6 8162 0.999998400 TI7W +2.6 3085 1.000002551 UA0S -2.0 6323 0.999998029 UA3REO +0.3 123 1.000000348 UP2L -4.3 2080 0.999995739 UY2RA +2.8 6337 1.000002753 V51YJ +2.0 1812 1.000001968 VE2WU* -0.1 3232 0.999999888 VE6AO -1.5 2453 0.999998524 VE6JY +1.8 4807 1.000001762 VE6WZ +3.3 4518 1.000003271 VE7CC +0.4 4216 1.000000351 VK2EBN +0.8 154 1.000000780 VK2GEL -0.5 219 0.999999487 VK3RASA +1.1 514 1.000001098 VK6ANC -1.3 1331 0.999998673 VR2FUN +1.3 810 1.000001317 VR2FUN-74 -0.4 600 0.999999623 VU2PTT +0.4 833 1.000000431 VU3ESV* +0.0 564 1.000000040 VY0ERC -0.5 17 0.999999511 W1NT-2 +0.4 8318 1.000000353 W1NT-6 +0.2 11142 1.000000212 W2LB +0.8 1310 1.000000803 W2MV +0.6 2165 1.000000598 W2NAF +0.9 3738 1.000000866 W3LPL +1.1 5573 1.000001082 W3OA +0.3 6894 1.000000322 W3RGA +0.2 7677 1.000000153 W3UA* -0.0 1860 0.999999984 W4AX +3.7 1020 1.000003704 W6YX +0.1 4131 1.000000098 W7MRF +5.7 1007 1.000005679 W8WTS -2.4 5176 0.999997584 W8WWV -2.1 6467 0.999997906 WA7LNW +1.3 5039 1.000001336 WB6BEE* +0.0 6341 1.000000009 WC2L +0.2 6617 1.000000218 WE9V -0.3 7834 0.999999654 WS3W* +0.5 1909 1.000000495 WZ7I* -0.1 8742 0.999999927 ZF1A +0.6 3685 1.000000570 ZL2KS -0.9 646 0.999999136 ZL3X -0.3 2019 0.999999679 Last updated 2023-02-06 00:17:27 UTC
Historical skimmer frequency accuracy
Below you will find historical accuracy data for the past ten 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 0205 0204 0203 0202 0201 0131 0130 0129 0128 0127 --------------------------------------------------------------------- 2E0EBM +0.4 3B8CW +0.0 +0.1 -0.0 -0.1 +0.1 -0.4 -0.3 -0.2 -0.9 -0.4 3D2AG -0.2 +0.3 +0.3 +0.1 +0.3 +0.3 +0.2 +0.5 -0.3 +0.0 3V8SS -1.7 -2.4 -2.7 -2.9 -3.0 -3.6 -3.2 -3.5 -2.6 5W1SA +1.3 +1.5 +1.0 +1.1 +1.1 +0.5 +0.5 +0.8 +0.4 7N4XCV +2.0 +1.2 +1.1 +0.8 +1.1 +1.1 -0.3 +1.5 +0.8 +0.8 9M2CNC -0.3 -0.8 -0.3 -0.1 -0.3 -0.2 -0.1 -0.9 -0.1 -0.6 AA4VV +0.0 -0.0 -0.0 -0.0 -0.0 -0.0 -0.0 -0.0 -0.0 -0.0 AC0C-1 -0.1 +0.0 +0.0 +0.0 -0.0 +0.1 +0.0 +0.1 -0.0 +0.1 BA6KC +2.6 +1.7 +1.5 +1.6 +1.6 -0.1 +1.6 +1.8 +2.7 +1.7 BD4QJP +0.8 +0.7 +0.0 +0.0 +1.8 +0.0 +0.9 +0.9 BD7DT +0.3 -0.2 -0.9 -1.1 +0.2 +0.7 +0.1 +1.2 +0.6 BD7JNA -0.6 +0.0 +0.0 +0.0 +0.5 +0.0 +0.0 +0.0 +0.7 -0.3 BD8BIN -2.5 BG4GOV +0.1 -0.8 +0.0 -0.8 -0.7 -0.5 -0.2 -0.7 BG4GOV3 +4.7 +5.1 +4.3 +2.4 BG4WOM -6.1 -6.5 -5.0 -6.2 -4.5 -5.5 -6.6 BG8FZU -0.9 -0.0 -0.0 +0.0 -0.1 -0.2 -0.5 -0.4 -0.6 -0.5 BH3BBJ +0.2 -0.2 +0.7 +0.3 +0.3 +0.1 +0.1 -0.2 BH4DEG +3.3 +2.8 +1.3 +2.0 +1.7 +1.7 +2.1 +3.6 +3.2 +2.0 BH4RRG0 +2.0 +1.8 +1.1 +0.9 +1.8 +0.7 +1.0 +1.4 +1.1 +0.5 BH4RRG +0.3 +0.1 +0.4 +0.1 -0.6 +0.1 +0.1 +0.3 +0.2 +0.3 BH4XDZ +0.5 -0.2 +0.4 +0.2 +0.2 +0.0 +0.3 +1.0 +0.5 -0.5 BH4XDZ-1 +1.0 +0.1 +0.4 -0.1 -0.6 +0.5 -0.1 +0.0 +0.6 +0.2 BI4MPH +8.9 +1.5 BI4RFP-1 +1.3 +0.7 +0.4 +0.6 +1.5 -0.4 +0.3 +0.3 +0.0 -0.5 BU2EQ +0.4 CT2IWW +0.9 +0.9 +0.0 CX6VM -1.8 -1.7 -1.4 -1.0 -0.3 -0.3 -1.0 -1.2 -0.8 -0.5 DC8YZ +0.0 -0.0 +0.0 +0.1 -0.0 +0.0 +0.1 -0.0 +0.0 -0.0 DD5XX -0.0 +0.4 +0.1 +0.0 -0.1 -0.4 -0.6 -0.5 -0.5 -0.3 DE1LON -0.9 -0.9 -0.5 -0.1 -0.2 -0.1 -0.2 -0.2 +0.1 -0.0 DE2SAX -0.7 -0.8 -0.4 -0.3 -0.3 -0.4 -0.3 -0.3 -0.4 -0.2 DF2CK -0.1 +0.1 +0.3 +0.1 +0.1 -0.2 -0.3 -0.5 -0.5 -0.4 DF7GB +0.0 -0.0 +0.0 +0.1 -0.0 -0.0 +0.0 +0.1 -0.0 +0.1 DG6FL -28.7 DJ2BC -0.7 -0.8 -0.8 -0.8 -1.0 -0.9 -1.1 -0.8 DJ9IE -0.0 +0.0 +0.0 +0.0 -0.3 -0.6 -3.6 DK0TE +16.7 +16.7 +16.5 +15.8 +16.4 +16.3 +8.3 +2.3 +1.9 +1.8 DK3UA -7.7 -8.3 -7.6 -7.5 -7.6 -7.6 -7.7 -7.9 -6.7 DK9IP -0.2 -0.2 -0.2 -0.2 -0.1 -0.1 -0.1 -0.1 -0.0 -0.1 DL0LA -0.0 -0.1 -0.0 -0.1 +0.0 -0.1 -0.1 +0.1 -0.1 -0.1 DL0PF +1.2 +1.5 +2.0 +1.8 +1.5 +1.7 +1.3 +1.2 +1.1 +1.3 DL1AMQ +0.7 +0.4 DL1AXX -0.1 -0.5 -0.6 -0.6 DL1HWS +0.3 +0.4 +0.2 +0.1 +0.2 +0.2 +0.2 +0.2 +0.3 +0.2 DL8LAS +1.2 +1.1 +0.8 +0.9 +1.0 +0.8 +1.0 +1.5 +0.7 DL8TG -0.1 -0.1 -0.0 -0.1 -0.2 -0.0 -0.2 +0.2 -0.2 +0.0 DL9GTB -0.7 -0.3 -0.2 DM5GG +0.3 +0.3 +0.2 +0.2 +0.2 +0.2 +0.2 +0.2 +0.2 +0.2 DM6EE +0.1 +0.1 +0.0 -0.1 +0.0 +0.0 -0.1 +0.0 -0.0 -0.1 DM7EE +0.0 +0.0 +0.0 -1.0 DO4DXA -0.1 -0.3 -0.3 -0.2 -0.1 -0.2 +0.6 -0.4 -0.2 DP6M -1.6 -1.6 -1.7 -1.5 -1.7 -1.3 DP7D +0.0 +0.0 +0.3 EA1DAV -0.8 -0.4 +0.1 +0.7 +0.8 +0.0 -0.8 -0.4 +0.0 -0.7 EA1RX -6.2 -6.3 -11.8 -15.0 -10.0 -11.5 -10.7 -11.1 -10.6 EA1URA +0.1 +0.1 +0.3 +0.1 +0.1 +0.0 -0.1 -0.3 -0.3 -0.0 EA2CW -0.3 +0.0 -0.5 -0.3 -0.1 -0.1 +0.1 -0.0 -0.4 -0.2 EA2RCF-4 +0.0 -0.0 -0.0 +0.0 -0.0 +0.1 +0.0 +0.0 +0.1 -0.0 EA5WU -0.7 -0.7 -0.4 -0.5 -0.7 -0.8 -0.7 -0.8 -0.7 -0.6 EA8BFK -0.4 -0.3 -0.4 -0.4 -0.4 -0.3 -0.3 -0.3 -0.3 EA8/DF4UE -0.5 -0.7 ES2RR -1.4 -0.9 +0.0 -0.1 +0.0 +0.0 -0.0 +0.0 -0.0 +0.0 EU1ST +4.1 +5.1 EY8ZE -1.2 -1.4 -0.8 -0.7 -1.1 -1.3 -1.4 F4EGZ/P -1.5 F4VSQ +3.8 +3.6 +3.5 +3.4 +3.7 +3.6 +3.6 F5AHD -3.1 +2.5 F6IIT -1.4 -1.5 -0.9 -1.5 -0.9 -1.3 -1.3 -1.6 -1.6 -1.3 F8DGY +0.0 -0.1 -4.9 -0.4 -0.2 G0KTN +0.3 +0.3 +0.3 +0.2 +0.2 +0.3 +0.3 +0.1 +0.2 +0.1 G0TAI -0.4 -0.7 -0.4 -0.7 -0.4 -0.5 -0.1 G0TMX +0.4 G3XBI +0.4 +0.3 +0.2 +0.1 +0.3 +0.2 +0.2 +0.3 +0.3 +0.4 G3YPP +0.1 +0.0 -0.1 +0.1 +0.1 +0.1 +0.2 +0.1 +0.0 -0.0 G4AON +1.0 +1.7 +1.4 +1.2 +0.9 G4HSO -3.0 -2.8 -2.2 -2.7 -3.3 -2.6 -1.9 -2.4 -3.1 -3.3 G4ZFE -1.3 -1.2 -0.3 -0.6 -0.6 -0.7 -0.6 -1.0 -1.0 -0.5 GI4DOH +0.0 +0.0 +0.1 +0.0 -0.3 +0.0 +0.1 +0.0 GM6DX +0.4 HA1VHF +0.6 +0.8 +0.7 +0.6 +0.5 +0.4 +0.4 +0.4 +0.7 +0.6 HA5PP +0.5 HA8TKS +0.2 +0.1 +0.2 +0.1 +0.2 +0.2 +0.2 +0.3 +0.1 +0.1 HB9BXE +0.4 +0.5 +0.4 +0.2 +0.3 +0.3 +0.1 +0.3 +0.2 +0.2 HB9CAT +4.7 +4.5 +4.4 +3.8 +4.4 +3.2 +3.4 +4.3 +4.0 HB9DCO +0.5 +0.3 +0.3 +0.1 +0.2 +0.1 +0.2 +0.3 +0.3 +0.4 HB9RB -7.2 +0.2 +0.7 -3.1 HG0Y -0.4 -0.2 -0.3 -0.1 -0.0 -0.4 -0.2 -0.3 -0.3 -0.1 HG2EWS +1.8 HG5FMV +0.3 +0.2 -0.1 -0.1 +0.5 +0.1 -0.0 HG8A -0.4 -0.7 +0.0 +0.8 +0.9 +0.8 -0.1 -0.4 -0.6 +0.5 HS/F8UKP +0.1 -0.2 -0.4 +0.1 -0.0 +0.2 -0.6 -1.1 -0.4 +0.1 IK3STG +4.5 +4.7 +3.9 +4.2 +2.9 +4.1 +4.7 +5.9 +4.1 +3.8 IK4VET +0.3 +1.0 +0.6 +0.5 +0.5 +0.1 -0.0 -0.1 -0.2 -0.1 JA4ZRK -0.7 -0.4 +0.0 +0.0 +0.0 +0.0 +0.0 +0.0 +0.1 -1.5 JG1DLY -0.5 -0.2 +0.0 JH4UTP +0.0 JH7CSU1 +4.6 +4.6 +3.4 +4.5 +2.7 +2.8 +3.4 +2.8 +3.5 +2.9 JI1HFJ -1.8 -3.7 -3.7 -3.4 -4.6 -3.3 -4.0 -3.4 -5.2 -5.2 JJ2VLY -2.6 -1.9 -1.1 -3.0 -5.3 -2.5 -4.3 -2.3 -2.4 -3.3 JN1ILK -0.6 -0.4 -0.9 -0.4 -1.5 -1.7 -1.6 +1.5 +0.0 -0.7 K1TTT -0.8 -1.3 -0.8 -0.6 -0.5 -0.6 -0.4 -0.4 -0.3 -0.5 K2PO/7 +0.7 +0.5 +0.5 +0.4 +0.3 +0.5 +0.3 +0.4 +0.7 +0.9 K3LR +2.5 +4.4 +4.7 +4.5 +3.4 +4.1 +3.8 +3.7 +4.1 +3.5 K3PA-1 +0.4 +0.7 +0.3 +0.5 +0.2 +0.4 +0.3 +0.3 +0.4 +0.7 K4PP +0.2 +0.0 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Anchor skimmers
The below skimmers use external frequency references and are confirmed to have continuous, high accuracy. Their accuracy is also confirmed against each other on a daily basis.
AA4VV DF7GB KM3T LZ3CB LZ4UX MM3NDH OE9GHV WB6BEE Last updated 2023-02-06 00:18:00 UTC
It is the owners of these skimmers who make this web page possible. Thank you.
To get good geographic coverage and a good size dataset, a two-step method is used for the analysis shown above. Since the second step also relies on spots from skimmers with slightly lower accuracy the displayed error for the anchor skimmers may not always be 0.0, even though they are perfectly accurate.
Software
The software powering this page can be found on github.