Subject: [SCIGN-0466] PIN2 Adaptor Change Subject
From: Paul F. Jamason
Date: 30 Oct 1998 14:35:16

******************************************************************************
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: [email-masked] (Paul Jamason)]