Date: Thu, 21 Aug 2008 10:13:18 -0400 From: "Jim.Ray" Subject: [IGSMAIL-5818]: Regarding changes at stations To: IGSMail , igsstation@igscb.jpl.nasa.gov Reply-to: jim.ray@noaa.gov Message-id: <48AD77FE.9090507@noaa.gov> Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit User-Agent: Thunderbird 2.0.0.16 (Windows/20080708) Sender: owner-igsmail Precedence: bulk ****************************************************************************** IGS Electronic Mail 21 Aug 07:13:20 PDT 2008 Message Number 5818 ****************************************************************************** Author: Jim Ray Dear Station Operators, Analysts are seeing a steady increase in unannounced or poorly announced changes in station configurations. This can cause serious problems in the data analysis and waste time for the analysts. It is important for us to have accurate metadata for all stations, but it absolutely critical for the IGS05 Reference Frame (RF) stations because their positions are held fixed to generate the Ultra-rapid and the Rapid products. Even though all station positions are freely adjusted in the Final products, the RF stations are still used to align each weekly frame. Nearly every week it seems that some stations must be manually rejected from the frame combination or from AC solutions due to incomplete or late reporting of station changes. Data users outside the IGS ACs may be badly affected and not even know. For those who do not know, the IGS05 RF stations are shown at: http://www.igs.org/network/refframe.html Please, for all RF stations (at least), it should be MANDATORY to report all information that could affect a station's position in an IGS Station Mail message BEFORE the changes are made. A standardized format would be helpful, such as (at least): Subject: changes planned at RF station XXXX Date of planned change: CCYY-MM-DD hh:mm UTC Receiver: current receiver New receiver: (if changed) Antenna: current antenna New antenna: (if changed) Antenna height offset: current value New offset: (if changed) Radome: current radome model or NONE New radome: (if changed) An updated site log should be filed as soon as possible (but never more than 24 hours after any changes). It is NOT SUFFICIENT to simply note that some unspecified changes will or have been made. Your cooperation is critical and greatly appreciated. Best regards, --Jim