From: Paul F. Jamason Date: 30 Oct 1998 14:35:16 Subject: [SCIGN-0466] PIN2 Adaptor Change Subject ****************************************************************************** SCIGN Electronic Mail Fri Oct 30 14:35:16 PST 1998 Message Number 0466 ****************************************************************************** Author: Paul F. Jamason Subject: PIN2 Adaptor Change Subject: PIN2 Adaptor Change Dear Colleagues, On October 22, 1998 the adaptor on PIN2 was changed from an older style machined-to-achieve-level adaptor to a new D3 SCIGN adaptor, in anticipation of SCIGN Dome testing. The change occurred at 1998:295:20:05 - 20:50. As the new adaptor is shorter the primary effect of this change is to have lowered the antenna by 4.47 cm. We don't expect that this adaptor change introduced a significant change in the horizontal position (perhaps 0.5 mm); the point of rotation for the leveling mechanism for both adaptors is about at the same point. Confirmation of both the vertical and horizontal offsets awaits processing of the GPS signals. More information will be forthcoming regarding the appropriate handling of the historical data record at this site in regard to the offset incurred. Please note that the new antenna height for this site is separate from the measurement given above; for the new SCIGN adaptor, antenna height is fixed and is measured from the raised nipple on the lower part of the antenna adaptor (peak of center support screw) to the bottom of the pre-amplifier on the antenna (BPA). This measurement is 0.0083 m. A problem we did discover: on October 22, 1998, the antenna was found twisted some 26 degrees west from true north (334 degrees, true) which we suspect happened on 1998:210:20 when the antenna mount was hit by equipment. This too we hope will be confirmed by subsequent analysis. The antenna is now aligned properly toward true north. The site log has been updated and is available via ftp from: ftp://lox.ucsd.edu/pub/docs/site_logs/pin2.log and from the web at: http://lox.ucsd.edu Thank you, Paul (Thanks to Frank Wyatt for this documentation - Paul) ------------------------------------------------------------ Paul F. Jamason Field Engineer, Southern California Integrated GPS Network Research Associate, Scripps Orbit and Permanent Array Center Institute of Geophysics and Planetary Physics, MC 0225 Scripps Institution of Oceanography University of California, San Diego 9500 Gilman Dr. La Jolla, CA 92093-0225 phone: 619-534-1750 (office) 619-534-7692 (lab) 619-981-4679 (cell) pager: 619-973-5491 fax: 619-534-9873 ------------------------------------------------------------ [Mailed From: pjamason@lox.ucsd.edu (Paul Jamason)]