Accession Number : ADA118525

Title :   Operation of Alaskan Long-Period Array.

Descriptive Note : Final rept. 1 Jul 75-30 Sep 76,


Personal Author(s) : Gudzin,M G

PDF Url : ADA118525

Report Date : 21 Dec 1976

Pagination or Media Count : 90

Abstract : The ALPA was operated 24 hours per day, 7 days per week from 1 July 1975 to 24 May 1976. (Author) During this time, the remote site fuel system design was reviewed for weaknesses that allowed development of fuel leaks, and a new improved design was developed. The AEE temperature control doors were replaced with new units that were designed and built to operate freely even though the AEE was warped severely by ground heaving. A full frequency calibration was conducted. Amplifier filter reliability was improved by replacing the quartz crystal used in the unit with one that did not fail when subjected to mechanical shocks like those received during commercial shipment. The old, vacuum-tube Develocorder oscilloscopes, which had deteriorated during many years of service, were replaced with new, simpler, solid-state oscilloscopes. Two types of propane fuel regulators were tested. Routine operation of the ALPA was terminated on 24 May 1976, when rollup work interrupted the operation of the telemetry links. Thereafter all work was directed to the complete rollup of remote sites 201, 205, 206, 301, 302, 304, 305, 306, 312, 316, 345, and 356, to the partial rollup of remote sites 101, 202, 203, 204, 303, 323, and 334. All work was completed on 30 September 1976. (Author)

Descriptors :   *Seismic arrays, *Alaska, Telemeter systems, Calibration, Ground level, Frequency, Temperature control, Leakage(Fluid), Heaving, Fuels, Doors, Topographic maps, Oscilloscopes, Regulators

Subject Categories : Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE