COMI Site Information
     IGEF-UNAM Instituto de Geofisica. 
     Department of Seismology  

0.   Form

     Prepared by (full name)  : Jose Antonio Santiago Santiago
     Date Prepared            : 22-FEB-2002
     Report Type              : UPDATE JUN-2006
     Prepared Using           : 


1.   Site Identification of the GPS Monument

     Site Name                : COMITAN
     Four Character ID        : COMI
     Monument Inscription     : 
     IERS DOMES Number        : Leica, no # 
     CDP Number               : (XXXX)               
     Monument Description     : TRIPODE
       Height of the Monument : (m)
       Monument Foundation    : STEEL RODS, CONCRETE BLOCK, ROOF
       Foundation Depth       : (m)
     Marker Description       : (CHISELLED CROSS/DIVOT/BRASS NAIL/etc)
     Date Installed           : 25-JAN-2002 20:00 UT
     Geologic Characteristic  : 
      Bedrock Type            : Biomicrita
      Bedrock Condition       : 
      Fracture Spacing        : 
     Notes                    : 
     Additional Information   : Located near to Comitan, Chiapas  
                             
                           

2.   Site Location Information

     City or Town             : COMITAN
     State or Province        : Chiapas
     Country                  : Mexico
     Tectonic Plate           : NA
     Approximate Position     
       X coordinate (m)       : -228.400677
       Y coordinate (m)       : -6121.23952
       Z coordinate (m)       : 1777.14277
       Latitude (deg)         : 16 16.912400 N
       Longitude (deg)        : 092 08.2108 W 
       Elevation (m)          : 1616.24m 
     Additional Information   :  
                              : Coordinate system used is (WGS84).
			      

3.   GPS Receiver Information

3.1  Receiver Type            : LEICA CRS1000
     Serial Number            : 30031
     Firmware Version         : v85.05 
     Date Installed           : 25-JAN-2002 23:00 UT
     Date Removed             : 
     Satellite System         : GPS
     Temperature Stabiliz.    : none
     Additional Information   : Antenna cable ~30m
    			      : 60MB Memory 
			      

3.x  Receiver Type            : 
     Serial Number            : 
     Firmware Version         : 
     Date Installed           : 
     Date Removed             : 
     Date Removed             : 
     Satellite System         : (GPS/GLONASS/GPS+GLONASS)
     Temperature Stabiliz.    : (none or tolerance in degrees C)
     Additional Information   :


4.   GPS Antenna Information

4.1  Antenna Type             : LEICA CHOKE RING AT504
     Serial Number            : 346
     Antenna Height (m)       : 
     Antenna Reference Point  : 
     Degree Offset from North : 0
     Antenna Radome Type      : LEICA dome
     Date Installed           : 25-JAN-2002 23:00 UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : Monument is drilled-braced type, installed in a reinforced
			      : concrete corner on the top of a brick station building
                              : based in a bedrock
                              : Coordinated system used is (WGS84)

4.x  Antenna Type             : 
     Serial Number            : 
     Antenna Height (m)       : (m)
     Antenna Reference Point  : (ARP/BCR/BPA)
     Degree Offset from North : 
     Antenna Radome Type      : 
     Date Installed           : (dd-MMM-yyyy hh:mm UT)
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : (multiple lines)


6.   Frequency Standard

6.1  Standard Type            : INTERNAL
       Input Frequency        :
       Effective Dates        : (CCYY-MM-DD/CCYY-MM-DD)
       Notes                  : (multiple lines)

6.x  Standard Type            : (INTERNAL or EXTERNAL H-MASER/CESIUM/etc)
       Input Frequency        : (if external)
       Effective Dates        : (CCYY-MM-DD/CCYY-MM-DD)
       Notes                  : (multiple lines)


11.   On-Site, Point of Contact Agency Information

     Agency                   : Departamento de Sismologia
     Mailing Address          : Instituto de Geofisica - UNAM
                              : Universidad Nacional Autonoma de Mexico 
                              : Coyoacan, 04510 Mexico, D.F.
     Primary Contact          
       Contact Name           : Dr. Vladimir Kostoglodov
       Telephone (primary)    : 5622-4126
       Telephone (secondary)  : 5622-4127
       Fax                    : 5616-2547
       E-mail                 : vladi@servidor.unam.mx
     Secondary Contact        
       Contact Name           : Jose Antonio Santiago Santiago
       Telephone (primary)    : 5622-4126
       Telephone (secondary)  : 5622-4127
       Fax                    : 5616-2547
       E-mail                 : santiago@geofisica.unam.mx
     Additional Information   : santiago@ssn.ssn.unam.mx



11.  More Information

     URL For More Information : 
http://tlacaelel.igeofcu.unam.mx/~vladimir/gpsred/gpsred.html 
http://tlacaelel.igeofcu.unam.mx/~vladimir/gpsred/comitan/comigps.html 
     Hardcopy on File         
       Site Map               : (Y)
       Site Diagram           : (Y)
       Horizon Mask           : (Y)
       Monument Description   : (Y)
       Site Pictures          : (Y)
     Additional Information   : (multiple lines)


     Antenna Graphics with Dimensions
                              
     
LEIAT504
L1/L2 Dorne Margolin antenna with chokerings
(designed after DORNE MARGOLIN T) 
                       +-------+                          <-- 0.1393
                     /     +     \                        <-- 0.1282 L2
                    |      +      |                       <-- 0.1093 L1
  +-----------------+-------------+------------------+    <-- 0.1020 TCR
  |                                                  | 
  |                                                  |
  |                                                  |
  |                                                  |
+-+--------------------------------------------------+-+  <-- 0.0380
+-------------------+-------------+--------------------+  <-- 0.1020 BCR
                    |             |
                    |             |
                    +------x------+                       <-- 0.000  BPA=ARP

<--                      0.3794                      -->


   ARP: Antenna Reference Point
   L1 : L1 Phase Center                   L2 : L2 Phase Center
   TCR: Top of Chokering                  BCR: Bottom of Chokering
   BPA: Bottom of Preamplifier