[IGSSTATION-2852]: HRAO: site repaired and updated site log

[David Maggert]

******************************************************************************
IGS Station Mail          12 Feb 11:45:34 PST 2009      Message Number 2852
******************************************************************************

Author: David Maggert, UNAVCO

Dear Colleagues,

The Hartebeesthoek RAO, Krugersdorp South Africa (HRAO) station has been 
repaired.  Initially it was believed that the antenna had failed or the 
connections had gone bad based on the feedback we were receiving from the 
Ashtech UZ-12 receiver.  So the original antenna "ASH701945E_M" was replaced 
with a Topcon CR-G3, however, the Ashtech UZ-12 receiver was still not detecting 
the Topcon antenna.  The Ashtech UZ-12 was replaced with another Ashtech UZ-12 
and the new receiver began tracking immediately.  Therefore, the original 
"ASH701945E_M" antenna was re-installed back at the site.  None of the test data 
from the Topcon antenna was saved, therefore the it was not recorded in the site 
log.

JPL has processed the data from HRAO since the Ashtech UZ-12 receiver swap and 
has noticed an ~2cm North shift in position.  After conferring with on-site 
personnel, it is believed that the Ashtech antenna was not fully or properly 
mounted at the time of the previous antenna installation.

The updated station coordinates provided by JPL are the following:

         X coordinate (m)       : 5085352.5970
         Y coordinate (m)       : 2668395.9920
         Z coordinate (m)       : -2768731.5510

The replacement Ashtech UZ-12 receiver is the following:

3.7   Receiver Type            : ASHTECH UZ-12
       Satellite System         : GPS
       Serial Number            : UC1200345010
       Firmware Version         : CN00
       Elevation Cutoff Setting : 4
       Date Installed           : 2009-01-15T00:00Z
       Date Removed             : (CCYY-MM-DDThh:mmZ)
       Temperature Stabiliz.    : none
       Additional Information   :

The first site log update was submitted on Feb 8th and contains the updated 
coordinates and receiver swap.

http://igscb.jpl.nasa.gov/igscb/station/oldlog/hrao_20090208.log
        Modified/Added Sections : 2, 3.6, 3.7

The second site log update contains the additional comments about the antenna 
re-installation in section 4.11 and an entry in section 9 regarding the observed 
shift in position.

http://igscb.jpl.nasa.gov/igscb/station/log/hrao_20090212.log
        Modified/Added Sections : 4.11, 9.3.1

Data publication will begin in a few days.  We apologize for any inconvenience 
this outage has caused.

Maintenance and operations of the HRAO station is a collaborative effort 
supported by JPL, UNAVCO, and the Hartebeesthoek RAO in Krugersdorp, with 
funding provided by NASA's Earth Surface and Interior Focus Area - Science 
Mission Directorate.

Best Regards,
David Maggert