<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Dear Colleagues,<div class=""><br class=""></div><div class="">We received raw Topcon data files for April 3rd that were translated incorrectly into RINEX files labeled March 27 (DOY 087). Therefore the good files DOY 087 were overwritten on April 4th with data from April 3rd. Those bad RINEX files were just replaced with the correct files for DOY 087. The IGS stations impacted were the following:</div><div class=""><br class=""></div><div class="">CHIL, CLAR, CMP9, HOLP, ROCK, SNI1, SPK1, TORP, UCLP, WHC1</div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">We apologize for the inconvenience. A detailed description from Lou Estey is provided below.</div><div class=""><br class=""></div><div class="">Best Regards,</div><div class="">David Maggert</div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><blockquote type="cite" class="">[2735] teqc +quiet +mds rg070403a<br class="">week: 1890<br class="">[2736] teqc -week 1890 +quiet +mds rg070403a<br class="">2016-03-27 00:00:00 2016-03-27 23:59:30 2441027 rg070403a<br class=""><br class="">... which is one week earlier than when the data is valid. This can be traced<br class="">to the code changes I made on March 25th (see<br class=""><a href="http://www.unavco.org/software/data-processing/teqc/log/log.html" class="">http://www.unavco.org/software/data-processing/teqc/log/log.html</a>) to correct the<br class="">GPS week reporting from SBF with navigation messages from the previous week.<br class="">The logic changes made on March 25th were absolutely necessary and are correct.<br class=""><br class="">However, in correcting all that for every format, including Topcon TPS, this<br class="">apparently brought to light an even more severe problem that these Topcon receivers<br class="">have (that just happened to work with the older incorrect logic in teqc).<br class=""><br class="">E.g. file rg070403a is data for 3 Apr 2016, which is GPS week 1891 (this week).<br class="">And this file does contain may GPS navigation messages for week 1891. However,<br class="">it has a bunch of the previous week 1890. This in itself is not a problem<br class="">and is what I was fixing details on March 25th. The problem is that these<br class="">Topcons, on Sunday, are reporting navigation messages also collected a week<br class="">prior to that. In particular, there are a bunch collected in the wee minutes<br class="">of GPS week 1889 (since ToW is just under 604800 == seconds in a week), but<br class="">these are messages for 00:00 on 27 Mar (GPS week 1890). The first old<br class="">message below does not cause trouble. because it is clearly for end of week<br class="">1890, but any of the following ones would trip teqc up and cause it to report<br class="">the starting week as 1890 because they are for the start of week 1890:<br class=""><br class="">866 -> 1890: ToC= 604784 ToE= 604784 ToW= 604770<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601110<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601140<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 599880<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601110<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601140<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 599880<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601110<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601140<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 599880<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601110<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 601140<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class="">866 -> 1890: ToC= 0 ToE= 0 ToW= 604410<br class=""><br class="">Now to figure out a stable way to code around this ...</blockquote></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div></body></html>