USNO Site Information Form International GPS Service for Geodynamics 0. Form Prepared by (full name) : Jim Ray (USNO) Date Prepared : 04-JUN-1999 Report Type : UPDATE : new antenna name used Prepared Using : 1. Site Identification of the GPS Monument Site Name : U.S. Naval Observatory Four Character ID : USNO Monument Inscription : no monument, ARP IERS DOMES Number : 40451S003 CDP Number : none Date Installed : 24-APR-1997 Geologic Characteristic : on edge of roof of 3-story building Bedrock Type : Bedrock Condition : Fracture Spacing : Notes : Additional Information : The antenna is mounted near the edge of the : roof (flat) of Building 52 (3 stories) at : the U.S. Naval Observatory inside Washington, : DC. There are no nearby geodetic markers or : control points. 2. Site Location Information City or Town : Washington State or Province : District of Columbia (DC) Country : U.S.A. Tectonic Plate : North American Approximate Position X coordinate (m) : 1112189.9031 Y coordinate (m) : -4842955.0319 Z coordinate (m) : 3985352.2376 Latitude (deg) : 38.9190 N Longitude (deg) : 282.9338 E Elevation (m) : 48.878 Additional Information : The epoch for the coordinates is 1997.653 and : is based on a survey of the USNO site made by : NOAA/NGS personnel during Aug-Sept 1997. 3. GPS Receiver Information 3.1 Receiver Type : ROGUE SNR-12 Serial Number : T246 Firmware Version : 3.2.32.4 Date Installed : 24-APR-1997 Date Removed : (dd-MMM-yyyy hh:mm UT) Additional Information : 24-APR-1997 to 12-AUG-1998: The receiver is in : the clock vault of Bldg 52A. The space is : environmental controlled but not stringently. : 12-AUG-1998 to present: The receiver is in an : environmentally controlled chamber within the : clock vault (Bldg 52A); specs are +/- 0.15 C : for temp. and +/- 1% for rel. humidity. 3.x Receiver Type : Serial Number : Firmware Version : Date Installed : (dd-MMM-yyyy hh:mm UT) Date Removed : (dd-MMM-yyyy hh:mm UT) Additional Information : (multiple lines) 4. GPS Antenna Information 4.1 Antenna Type : AOAD/M_T Serial Number : 309 Antenna Height (m) : 0.0 Antenna Reference Point : ARP Degree Offset from North : oriented North but not measured Antenna Radome Type : none Date Installed : 24-APR-1997 Date Removed : 12-NOV-1998 Additional Information : Antenna cable 24-APR-1997 to 12-AUG-1998: : Intercomp RG-217/U -- physical length : 293 feet (89.31 m), mostly exposed to full : sun running along rooftop of Bldg 52 : specifications: : Velocity factor 0.66 : Capacitance 30.8 pf/foot : Loss at 1225 MHz 6.5 dB/100 foot : Loss at 1575 MHz 7.6 dB/100 foot : Electrical Length Change versus Temperature: : spec is between 0.50 ps/m/C and 1.24 ps/m/C; : USNO measurement of similar RG-217 cable : gave 0.53 ps/m/C : Antenna cable 12-AUG-1998 to present: : Andrew FSJ1-50A (35422-33 phase stabilized) : 1/4 inch Superflexible Foam Dielectric : Heliax -- physical length 296.5 feet : (90.37 m), mostly run in ceiling of 3rd : floor of Bldg 52; measured electrical : length is 373 +/- 3 ns : specifications: : Velocity factor 0.84 : DC resistance 2 to 3 ohms per 1000 foot : Capacitance, 24.2 pF/foot : Inductance, .061 uH/foot : Loss at 1250 MHz 6.77 dB/100 foot : Loss at 1500 MHz 7.47 dB/100 foot : Electrical Length Change versus Temperature: : 400 PPM over (-40 to 30 C) or 5.7 PPM/C : => 0.02 ps/m/C 4.2 Antenna Type : AOAD/M_T Serial Number : 309 Antenna Height (m) : 0.0 Antenna Reference Point : ARP Degree Offset from North : oriented North but not measured Antenna Radome Type : none Date Installed : 12-NOV-1998 Date Removed : (dd-MMM-yyyy hh:mm UT) Additional Information : Antenna removed at ~13:45 UTC to repair the : parapet coping (painted metal) on the roof : edge immediately below the antenna. The : same antenna was reinstalled in the same : location about 30 minutes later. 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) 5. Local Site Ties 5.1 Monument Name : none Site Ref CDP Number : none Site Ref Domes Number : none Differential Components from GPS Mark to Site Reference (ITRS) dx (m) : (m) dy (m) : (m) dz (m) : (m) Accuracy (mm) : (mm) Date Measured : (dd-MMM-yyyy hh:mm UT) Additional Information : (multiple lines) 5.x Monument Name : Site Ref CDP Number : (XXXX) Site Ref Domes Number : (XXXXXXXXX) Differential Components from GPS Mark to Site Reference (ITRS) dx (m) : (m) dy (m) : (m) dz (m) : (m) Accuracy (mm) : (mm) Date Measured : (dd-MMM-yyyy hh:mm UT) Additional Information : (multiple lines) 6. Frequency Standard 6.1 Standard Type : steered H-MASER Frequency : 5 MHz Effective Dates : 24-APR-1997 Notes : reference signal from an H-maser (MC3) located : in Bldg 52 which is steered to the USNO Master : Clock (MC2), the realization of UTC(USNO); : calibration data for MC3-MC2 are available; : calibration of clock offset between MC3 and : GPS receiver being investigated. Cable for 5MHz : signal is RG-223 with thermal coeff. of 3000 : PPM over (+10 to 30 C range) or 150 PPM/C. The : 1 PPS output signal is monitored and compared : with reference to determine clock offsets when : receiver resets. : On 12-NOV-1988 the trigger level for the 1 PPS : monitoring was changed from 1 V to 0.5 V. 6.x Standard Type : (H-MASER/CESIUM/QUARTZ/INTERNAL/RUBIDIUM) Frequency : Effective Dates : (dd-MMM-yyyy - dd-MMM-yyyy) Notes : (multiple lines) 7. Collocation Information 7.1 Instrumentation Type : none Status : Effective Dates : Notes : 7.x Instrumentation Type : (DORIS/GLONASS/PRARE/SLR/VLBI) Status : (PERMANENT/MOBILE) Effective Dates : (dd-MMM-yyyy - dd-MMM-yyyy) Notes : (multiple lines) 8. Meteorological Instrumentation 8.1 Humidity Sensor Model : Lithium chloride dew point units Manufacturer : Honeywell probes/General Eastern units Data Frequency : 10 sec Accuracy (% rel h) : dew point to 5 deg F Effective Dates : (dd-MMM-yyyy - dd-MMM-yyyy) Notes : probes are treated with lithium chloride activated solution and dried 8.2 Pressure Sensor Model : Digital barometer (model 361) Manufacturer : Setra Data Frequency : 10 sec Accuracy (mbar) : 0.1 mm mercury Height Diff to GPS (m) : unknown Effective Dates : (dd-MMM-yyyy - dd-MMM-yyyy) Notes : all met sensors are located at USNO in : Building 7 (the Transit House for 6-inch : transit circle); air temp, air pressure, and : dew point read every 10 seconds; contact for : met data is Theodore J. Rafferty, Astrometry : Dept., USNO (TJR@sicon.usno.navy.mil) 8.3 Temperature Sensor Model : Platium Res Probes (model CT-807-A) Manufacturer : Hy-cal Data Frequency : 10 sec Accuracy (deg C) : (deg C) Effective Dates : (dd-MMM-yyyy - dd-MMM-yyyy) Notes : (multiple lines) 8.4 Water Vapor Radiometer : none Manufacturer : Distance to GPS (m) : (m) Elev Diff to GPS (m) : (m) Effective Dates : (dd-MMM-yyyy - dd-MMM-yyyy) Notes : (multiple lines) 8.5 Other Instrumentation : The USNO backup Master Clock is located in the : same building as this GPS receiver. The : differential time offset between the Master : Clock and the GPS antenna will be eventually : be monitored and used to calibrate the receiver : clock time directly to UTC(USNO). 9. On-Site, Point of Contact Agency Information Agency : U.S. Naval Observatory Mailing Address : TS Dept. : 3450 Massachusetts Ave., NW : Washington, DC 20392-5420 Primary Contact Contact Name : Paul Wheeler (USNO) Telephone (primary) : 202-762-1581 Telephone (secondary) : Fax : E-mail : paul@tsee2.usno.navy.mil Secondary Contact Contact Name : Jim Ray (USNO) Telephone (primary) : 202-762-1444 Telephone (secondary) : Fax : 202-762-1563 E-mail : jimr@maia.usno.navy.mil Additional Information : Regional Data Center is NOAA GODC Regional Data Center Contact Contact Name : Linda Nussear (NOAA) Telephone (primary) : 301-713-2852 Telephone (secondary) : Fax : 301-713-4475 E-mail : linda@gracie.grdl.noaa.gov 10. Responsible Agency (if different from 9.) Agency : (same as above in 9.) Mailing Address : (multiple lines) Primary Contact Contact Name : Telephone (primary) : Telephone (secondary) : Fax : E-mail : Secondary Contact Contact Name : Telephone (primary) : Telephone (secondary) : Fax : E-mail : Additional Information : (multiple lines) 11. More Information URL for More Information : http://tycho.usno.navy.mil/gpscp.html Hardcopy on File Site Map : N Site Diagram : N Horizon Mask : N Monument Description : no monument Site Pictures : N Additional Information : (multiple lines) Antenna Graphics with Dimensions TurboRogue: DORNE MARGOLIN T (AOAD/M_T) ----- / + \ <-- 0.128 L2 | + | <-- 0.110 L1 +--------------------------------------------------+ <-- 0.102 TCR | | | | | | | | +-+--------------------------------------------------+-+ <-- 0.038 +-------------------+-------------+--------------------+ <-- 0.035 BCR | | =| | +------x------+ <-- 0.000 ARP <-- 0.381 --> ARP: Antenna Reference Point L1 : L1 Phase Center L2 : L2 Phase Center TCR: Top of Chokering BCR: Bottom of Chokering