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Instructions for filling out IGS site logs (April 2011)

See log form at


Please prepare site logs in plain ASCII.

Line length is limited to 80 characters.

See for
parsing instructions.  When ready, submit site logs by sending as a
plain text email message to  Site logs 
are usually handled by the CB within about one business day.

Date and time formats within the site log follow the basic format 
"CCYY-MM-DDThh:mmZ" from  ISO 8061; see
As a summary, CC=2 digit century
              YY=2 digit year
              MM=2 digit month
              DD=2 digit day of month
              T=date/time separator
              hh=2 digit hour
              mm=2 digit minutes of hour
              Z=UTC indicator
              /=separator when begin & end times are given

A date without a time is specified like "2003-07-30", not "2003-07-30Thh:mmZ"

Latitude/Longitude formats are aligned to ISO 6709:
  Lat:  +/-DDMMSS.SS
  Long: +/-DDDMMSS.SS
A + or - sign is required.  Leading zeroes must be used as appropriate
to maintain the DDMMSS and DDDMMSS format.

Valid latitude range is -90 degrees to +90 degrees.
Valid longitude range is from -180 degrees to (infinitesmally less than) +180

"etc" indicates you may enter any relevant answer, not just a choice 
ofthe suggestions shown.

"F7.4," "A4" and so on indicate the  FORTRAN-style format which the 
response should have.
     Example     12345.7 = F7.1
                    ABCD = A4

Blocks which have a "N.x" definition (namely sections 3-10) should 
always have the complete historic set of information; when a change is 
made, the previous information is left (for example in section 3.1) 
and the new information is placed in a new block numbered 3.2.  Please 
leave the .x  sections uncompleted to remind yourself of the format 
when the next change occurs.  

Please remove the response hints  such as "(F7.4 N/S)" as you fill out 
the log (except in the .x sections and Date Removed fields for 
currently installed equipment, which you will not alter).  If an
answer in an optional field is unknown, try to learn the answer for 
the next log update.  

If you have any questions not answered here, please feel free to 
contact the IGS Central

Special Instructions  by section

0.   Form

If Update:
Previous Site Log       : (ssss_CCYYMMDD.log)
     If the site already has a log at the IGS Central Bureau, enter 
     the filename currently found under     
     ssss = 4 character site name

If Update:
Modified/Added Sections : (n.n,n.n,...)
     Enter the sections which have changed from the previous version 
     of the  log.  Example: 3.2, 4.2

1.   Site Identification of the GNSS Monument

IERS DOMES Number        : (A9)
     This is strictly required.  See to obtain one.

Monument Description     : (PILLAR/BRASS PLATE/STEEL MAST/FICTIVE/etc)
     Enter one or more elements as necessary to describe the monument.

Additional Information   : (multiple lines)
     Suggestions: electrical isolation

2. Site Location Information

Approximate Position (ITRF)
     This should be to a one meter precision.
     The elevation may be given to more decimal places than F7.1.  7.1 is a
        minimum for the SINEX format.
3.  GNSS Receiver Information

Receiver Type            : (A20, from; see instructions)
     Please find your receiver in and use 
     the official name, taking care to get capital letters, hyphens, 
     etc. exactly correct.  If you do not find a listing for your 
     receiver, please notify the IGS Central Bureau 

Satellite System         : (GPS+GLO+GAL+BDS+QZSS+SBAS)
     Indicates the receiver capability with the installed firmware.
     Acronyms can be found in the standard.

Serial Number            : (A20)
     Keep the 5 significant characters of the serial number field in 
     SINEX in mind: do not enter "S/N 12345" instead of "12345" since 
     valuable information will be lost.

Firmware Version         : (A11)
     Keep the 11 significant characters of the field in SINEX in mind.

 Elevation Cutoff Setting : (deg)
     Please respond with the tracking cutoff as set in the receiver, 
     regardless of terrain or obstructions in the area.

Temperature Stabiliz.    : (none or tolerance in degrees C.)
     This refers to the temperature of the room in which the receiver 
     is housed.

Date Removed             : (CCYY-MM-DDThh:mmZ)
     In the block for the receiver currently in operation, leave this 
     line as is to remind yourself of the format when the next receiver 
     change is made.

4.   GNSS Antenna Information

Antenna Type             : (A20 from; see instructions)
     Please find your antenna in and 
     use the official name, taking care to get capital letters, hyphens, 
     etc. exactly correct.  If you do not find a listing for your 
     antenna, please notify the IGS Central Bureau 
     (  Please do not use antenna names from a 
     "Previously valid" section.  Choose the corresponding new antenna 
     name instead.  The radome code from must be indicated
     in columns 17-20 of the Antenna Type, use "NONE" if no radome is

     The antenna+radome pair must have an entry in with zenith-
     and azimuth-dependent calibration values down to the horizon. If not,
     notify the CB.  

Serial Number            : (A20)
     Keep the 5 significant characters of the serial number field in 
     SINEX in mind: do not enter "S/N 12345" instead of "12345" since 
     valuable information will be lost.

Antenna Reference Point  : (BPA/BCR/XXX from "antenna.gra"; see instructions)
     Locate your antenna in the file 
     Indicate the three-letter abbreviation for the point which is 
     indicated equivalent to ARP for your antenna.  Contact the Central 
     Bureau ( if your antenna does not appear.

Marker->ARP Up Ecc. (m)  : (F8.4) 
     This is the antenna height measured to an accuracy of 1mm 
     and defined as the vertical distance of the ARP from the marker 
     described in section 1.

Marker->ARP North Ecc(m) : (F8.4)
Marker->ARP East Ecc(m)  : (F8.4)
     These must be filled in if nonzero.

Alignment from True N    : (deg; + is clockwise/east)
     The positive direction is clockwise, so that due east
     would be equivalent to a response of "+90"

Antenna Radome Type      : (A4 from; see instructions)
     Place a Radome code from here.  
     "NONE" indicates there is no external radome.  If an antenna has
     a cover which is integral and not ordinarily removable by the 
     user, it is considered part of the antenna and "NONE" is to 
     be used for the radome code. The radome code used here has to be
     the same as the one in the columns 17-20 of the Antenna Type

Date Removed             : (CCYY-MM-DDThh:mmZ)
     In the block for the antenna currently in operation, leave this 
     line as is to remind yourself of the format when the next antenna 
     change is made.

5.   Surveyed Local Ties
Local ties to other markers on the site should be determined in ITRF
coordinates to 1mm precision in all 3 dimensions.  Offsets are given
in geocentric Cartesian coordinates (ITRF). 

8.   Meteorological Instrumentation
       Height Diff to Ant     : (m)
Positive numbers indicate meteorological instrument is ABOVE GPS antenna.

12.  Responsible Agency (if different from 11.)
The primary contacts listed here should always be the first choice for 
questions about operation of the site.  This person will receive 
automated emails regarding site log or RINEX errors and should be 
someone who can answer  questions about the configuration and data 
delivery for this site.

13.  More Information
     Primary Data Center      :
     Secondary Data Center    :
Please list the DC where the station's data ordinarily goes first as
"Primary."  Use "Secondary" either for a second location where
the station's data always goes, or would go in the case of a
long-term failure with the Primary DC.

Select primary and secondary data centers via centers.html and enter
the abbreviation of the DC name.  A geographically-
or functionally- related center is generally preferred.  The secondary DC
is where data would be sent if the primary were unavailable for an extended
period.  The switchover does not need to be automated, but data transfer
procedures should be verified.

     URL for More Information : 
This will be linked on the igscb's page for this site.  It is
not necessary to include "http://". 

Photos are mandatory. Send all available photos of antenna, radome, 
placement and all relevant photos to the CB. Contact the CB if you have photos
which cannot be hosted on a site web page.

     Additional Information:
Anything you feel is important.  Some possibilities to consider are:
- Elevation mask table indicating physical mask effects such as
 AZ   ELEV    AZ   ELEV    AZ   ELEV    AZ   ELEV
 10     8     20    12     30    10     40     8
 50     5     60    12     70     8     80     8
 90     5    100     5    110     5    120     5
130     5    140     5    150     8    160     8
170     5    180     3    190     5    200     8
210     8    220     8    230     5    240     5
250     5    260     8    270    10    280    12
290    12    300    12    310    12    320     8
330     5    340     5    350     8    360     8
(This could also be kept at your local www site and referred to
by URL in the log).