Welcome to CDC Stacks | EM Location System Prototype And Communication Station Modification - 8874 | National Institute for Occupational Safety and Health
Stacks Logo
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.
 
 
Help
Clear All Simple Search
Advanced Search
EM Location System Prototype And Communication Station Modification
  • Published Date:
    7/1/1973
Filetype[PDF - 7.18 MB]


This document cannot be previewed automatically as it exceeds 5 MB
Please click the thumbnail image to view the document.
EM Location System Prototype And Communication Station Modification
Details:
  • Description:
    A prototype EM Location System was fabricated and tested at the Geneva Mine near Dragerton, Utah. This system consisted of six manpack transmitters and six manpack receivers covering the frequency band from 900 Hz to 2900 Hz as well as a six channel receiver designed for use in a helicopter. Tests showed that EM signals from lightweight (314 lb) transmitters could be detected both on the surface and from a helicopter through -2 as much as 1650 ft of relatively high conductivity (2 X 10 mhos/m) over- burden. Furthermore, the resulting field strength profiles could be used to determine source location to within 150 ft of the actual surveyed location in the mine. Modifications were made to a Monitoring, Locating and Communications System being tested at the Bruceton Mine, Pittsburgh, Pennsylvania. These modifications have improved the performance and quality of the paging and voice telephony mode of the system. Subsurface receiver modifications have improved reception of voice downlink signals.

  • Supporting Files:
    No Additional Files
No Related Documents.
You May Also Like: