From: Ken Hudnut - USGS, Pasadena Date: 4 Aug 1995 11:54:54 Subject: [SCIGN-0088] New station and other changes Subject ****************************************************************************** SCIGN Electronic Mail Fri Aug 4 11:54:54 PDT 1995 Message Number 0088 ****************************************************************************** Author: Ken Hudnut - USGS, Pasadena Subject: New station and other changes Subject: New station and other changes --------------------------------------------------------- DAM1: ----- As of 8-3-95, there is a new continuous GPS station running, called DAM1. It is an Ashtech low-power Z-12 unit with Ashtech-manufactured choke ring Dorne-Margolin antenna, purchased by Los Angeles County. This station has the antenna mounted on top of a 1-story reinforced concrete structure that is built on the abuttment mass at the south side of Pacoima Dam. The second station on the dam, which will be located out on the dam arch (slightly north of the spillway center) will be installed in late August (pending several items). Here is some preliminary information on the new station DAM1: rec'r S/N LP00221; antenna S/N 11931 antenna height (to base of pre-amp) 9.80 cm It is located at approx. 34.3336 N, 118.3974 W, 620 m (from receiver C/A during installation) The antenna is mounted on a threaded steel pin, and the datum mark for measuring the antenna height is a machined groove in the pin. --------------------------------------------------------- CMP9: ----- Today, 8-4-95, we are doing minor work at CMP9. The modem was swapped out, and there is break in the data at approx. 18:00-19:00 GMT, indicating work on the modem & antenna mount. The field work is in progress, and we will report if there is any change in the antenna height after this adjustment (we expect there will be no change). --------------------------------------------------------- Search for a New Station: ----------------------- On July 25, 1995, we tested tracking at Mount Disappointment with the Ashtech Z-12 unit, and were unable to track there. We have several reasons to favor putting this unit at Table Mountain observatory 4 miles NW of Wrightwood; 1) we maintain seismic equip- ment at this location, 2) it is along the line of the proposed Profile Array, and 3) it is well located for obtaining a rate of contraction across the more eastern portion of the Sierra Madre/Cucamonga fault system. If there are objections to putting the unit at Table Mountain, please let me know. We would like to go ahead and install it there later this month. --------------------------------------------------------- [Mailed From: Ken Hudnut ]