From: Dennis McCarthy Subject: [IGSMAIL-1598] USNO Site Date: Tue, 13 May 1997 8:35:36 PDT ****************************************************************************** IGS Electronic Mail Tue May 13 8:35:36 PDT 1997 Message Number 1598 ****************************************************************************** Author: Dennis McCarthy Subject: USNO Site A new permanent GPS tracking site has been installed at the U.S. Naval Observatory. The new station is named `USNO' and it is mounted on the rooftop of Building 52 at the Observatory, located near downtown Washington, DC. The geodetic reference point is the ARP rather than a conventional monument. This receiver uses a reference 5 MHz signal from the steered H-maser which serves as the realization of the UTC(USNO) timescale. We intend to calibrate the clock offset from the H-maser to the GPS antenna in order to provide a direct link between UTC(USNO) and the time standards at the tracking stations of the IGS global network as well as the GPS satellites themselves. The NOAA GODC group has kindly assisted with the installation of this GPS receiver and will serve as the Regional Data Center for data distribution. USNO data are available at CDDIS starting 01 May 1997. A copy of the Site Information Form is attached below. Dennis McCarthy Director of Time, U.S. Naval Observatory ----------------------------------------------------------------------------- USNO Site Information Form International GPS Service for Geodynamics 0. Form Prepared by (full name) : Linda Nussear (NOAA), Jim Ray (USNO) Date Prepared : 12-MAY-1997 Report Type : NEW 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) : 1112189.117 Y coordinate (m) : -4842954.301 Z coordinate (m) : 3985351.389 Latitude (deg) : 38.9190 N Longitude (deg) : 282.9338 E Elevation (m) : 47.654 Additional Information : (multiple lines) 3. GPS Receiver Information 3.1 Receiver Type : TurboRogue SNR12 Serial Number : T246 Firmware Version : 3.32.1.4 Date Installed : 24-APR-1997 Date Removed : (dd-MMM-yyyy hh:mm UT) Additional Information : (multiple lines) 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 : DORNE MARGOLIN T Serial Number : 309 Antenna Height (m) : (m) Antenna Reference Point : ARP Degree Offset from North : oriented North but not measured Antenna Radome Type : none Date Installed : 24-APR-1997 Date Removed : (dd-MMM-yyyy hh:mm UT) Additional Information : (multiple lines) 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 USNO Master Clock, the realization of UTC(USNO); calibration of clock offset to be established later 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 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 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 : 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 ----- / + \ <-- 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 TGP: Top of Ground Plane BGP: Bottom of Ground Plane TPA: Top of Preamplifier BPA: Bottom of Preamplifier TOP: Top of Pole -- Dennis D. McCarthy dmc@maia.usno.navy.mil Director, Directorate of Time phone: (202) 762-1837 U.S. Naval Observatory fax: (202) 762-1563 Washington, DC 20392-5420 [Mailed From: Dennis McCarthy ]