Subject: [IGSMAIL-0468] St. Croix (CRO1) GPS
From: Tom Clark (NASA/GSFC)
Date: Tue, 1 Feb 1994 10:01:51 PST

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IGS Electronic Mail      Tue Feb  1 10:01:51 PST 1994      Message Number 0468
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Author: Tom Clark (NASA/GSFC)
Subject: St. Croix (CRO1) GPS

Subject: St. Croix (CRO1) GPS

In early January, Mark Bryant made the trek to St. Croix, US Virgin Islands
(hardship duty to leave the Washington DC area in January!) to install a
TurboRogue at the St. Croix VLBI station in support of the January CONT94 
VLBI campaign and the February Caribbean and South American DOSE invest-
igations. The installation is a "standard" NASA FLINN/IGS concrete pier
designed for permanent, long-term use. Site survey ties have not yet been
done, but I have attached the standard IGS site information form which
Mark prepared for me.

Geoff Blewitt and I have an approved DOSE investigation to install permanent
FLINN GPS receivers at all ten VLBA sites. The first two such sites (which
have been operational for some time) were Pie Town (New Mexico) and North 
Liberty (Iowa). Unfortunately NASA Headquarters has made the decision that
these first two sites will be the only ones so equipped. St. Croix, Mauna
Kea (Hawaii) and Brewster (Washington) are the next on the priority list
that Geoff and I established.

Thus the St. Croix installation must be regarded as only temporary. Ruth
Neilan and Steve Dinardo put forth super-human efforts to make a receiver
available for a couple of months, but current plans call for St. Croix to
leave the air the end of February.

If you find it desirable to have St. Croix (or any of the other VLBA sites)
implemented with permanent receivers, please let Geoff and me know. It would
also be useful for you to make your desires known to John LaBrecque at NASA
Headquarters ( [email-masked] ).

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**********************************
     SITE INFORMATION FORM
**********************************

0. Form

        Prepared by (full name): Dr. Thomas A. Clark
                                 Space Geodesy Branch
                                 Code 926.9
                                 NASA Goddard Space Flight Center
                                 Greenbelt MD 20771
                                 [email-masked]
        Date                   : February 1, 1994
        Report type            : New
          (NEW or UPDATE)
 
1. Site Identification of the GPS monument

        Site Name              : St. Croix VLBA
        4 char ID              : CRO1
        Monument Inscription   : St. Croix VLBA RM 1  
        IERS DOMES Number      : none assigned yet
        CDP Number             : JPL 4023
        Date                   : 1994
        Additional information : The monument is a 0.457m diameter stainless
                                 steel plate set in a 0.762m diameter concrete
                                 monolith that projects 0.635m above grade. The
                                 monument is located approximately 82m
                                 northwest of the 25m VLBA antenna.

2. Site Location

        City                   : Christiansted
        Country                : United States Virgin Islands (USA)
        Tectonic Plate         : Caribbean
        Additional information : The site is located at the NRAO VLBA facility
                                 on the northeast tip of St. Croix.

3. GPS Receiver

        Type                   : TurboRogue SNR-8000
        Serial Number          : T-133
        Firmware Version       : 2.8
        Date                   :

4. GPS Antenna

        Type                   : Dorn-Margolin T
        Serial Number          : 133
        Date                   :

        Vertical Antenna Height: 6.14 cm
        Antenna Reference Point: bottom of pre-amp
        Date                   : January 16, 1994

5. Local Site Ties
        
Monument        CDP    DOMES              Components      Accuracy Date
Name          Number  Number       dX       dY      dZ     mm yy-mm-dd
............  ....... ........   ........ ........ ........ .. .. .. ..
............  ....... ........   ........ ........ ........ .. .. .. ..
............  ....... ........   ........ ........ ........ .. .. .. ..

Differential coordinates from the GPS monument to the reference and 
other monuments. The components are parallel to the XYZ-axes of the 
global geocentric reference system ITRF (WGS-84).

Site ties currently not available.

"Accuracy" is estimated accuracy of local survey (millimeters).

6. Frequency standard

        H-maser / x /   Cesium /   /    Quartz /   /     Internal /   /
        Other (specify)        :
        Date                   : January 12, 1994

        (Mark with 'X')

7. Collocation

        SLR    /   /    VLBI  /x /     DORIS  /  /     PRARE    /  /  

        Other GEOPHYSICAL Instrumentation (specify)        :

        Other (specify)        :

        (Mark with 'P' for permanent, 'M' for mobile collocation)

8. On-site, Point of Contact Agency Information 

        Agency                 : National Radio Astronomy Observatory (NRAO)
        Contact                : John Williams/Ronald Lindsey
        Address                : NRAO St. Croix VLBA Station
                                 P.O. Box 24878
                                 Gallows Bay Station, Christiansted
                                 St. Croix, USVI  00824-0878
        Telephone              : (809) 773-4448
        E-mail                 : [email-masked]
        Fax                    :

9. Responsible Operations Agency 
   (if different from item 8)

        Agency                 : JPL
                                
        Contact                : Steve Dinardo
        Address                : 4800 Oak Grove Drive
                                 Pasadena, CA  91109
        Telephone              : (818) 354-3429
        E-mail                 : [email-masked]
        Fax                    : (818) 393-4965

10. Please insert here the character graphics corresponding to the 
antenna type.

             TurboRogue: DORNE MARGOLIN T

                         -----  
                     /     +     \                        <-- 0.128  L2
                    |      +      |                       <-- 0.110  L1
  +--------------------------------------------------+    <-- 0.102  TCR
  |                                                  |
  |                                                  |
  |                                                  |
  |                                                  |
+-+--------------------------------------------------+-+  <-- 0.038
+-------------------+-------------+--------------------+  <-- 0.035  BCR
                    |             | 
                   =|             |  
                    +------x------+                       <-- 0.000  ARP

<--                      0.381                       -->

11. Hard copy information

    Please mark 'X' if on file or date expected to be available.

        Site Map               : x
        Site Diagram           : x
        Horizon Mask           : 1994
        Monument description   : x
        Site pictures          : x

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