****************************************************************************** dorismail 07-Aug-2006 16:29:56 Message No 0458 ****************************************************************************** Author: "H. Fagard" Subject: Equipment upgrade and antenna raising at Arequipa (Peru) Dear Colleagues, The DORIS station at Arequipa, initially installed in 1988 and renovated in November 2001, has been down since August 2003 following a beacon failure. Because of the temporary closure of the host agency for almost two years, it was not possible to send a new beacon before the beginning of 2006. Then the equipment dispatch and customs clearance took a while, and the equipment was eventually installed last week. The beacon is now a third generation one. The Starec antenna, installed in 2001 on a concrete pillar was not changed, but it was raised by 15 cm using a special device, in order to be able to connect the cables without using the N-type bent adaptors usually required when the antenna is installed on a concrete pillar. Such adaptors, which are designed for laboratory-environment, not external use, are suspected to cause a signal attenuation in the long term due to corrosion. This is a trial installation in order to validate the new device, before possibly installing it at other pillar-equiped DORIS stations. The acronym for the new reference point is ARFB. Transmissions from the new beacon and new antenna position started on August 2. The DOMES number for the new antenna reference point is 42202S007. The vector from AREB to ARFB is exactly dE = dN = 0; dh = 0.150 m. Hence the (ITRF2000, 1997.0) coordinates for ARFB: X = 1942803.322 m Y = -5804071.548 m Z = -1796922.279 m (sigma: 1 cm) I remind you that the ITRF2000 velocities for this site are: VX = 0.0118 m/y VY = -0.0010 m/y VZ = 0.0137 m/y Best regards, Herve Fagard -- ====================================================================== Herve FAGARD e-mail : herve.fagard@ign.fr Institut Geographique National 94165 SAINT-MANDE CEDEX PHONE : + 33 1 43 98 81 48 FRANCE FAX : + 33 1 43 98 84 50 ====================================================================== Please do not reply directly to this message, but send comments and suggestions to IDS.central.bureau@cls.fr