Improvements for Mine Carrier Phone Systems. Technical Services for Mine Communications Research

Details

• Personal Author:
  Emslie, Alfred G. ; Foulkes JD ; Lagace, Robert L. ; Martin PG ; Spencer, Richard H.
• Description:
  Based on interviews and discussions with knowledgeable people, laboratory experiments, and in-mine measurements, it was determined that the major impediment to good carrier phone system performance is the extreme signal attenuation found on the trolley wire-rail largely caused by the many bridging loads. Three means are identified to help overcome the performance difficulties: the low impedance trolley wire, a method of improving performance by capacitively loading the transmission line; the dedicated wire, a low-loss means of extending trolley signal coverage; and the use of isolators to remove the offending bridging loads at the carrier frequency. Other subjects treated in the report are design reviews of hardware, guidelines for the use of information in the report, recommendations, and a description of a probe for measuring trolley wire current. [Description provided by NIOSH]
• Subjects:
  Occupational Health Safety
• Series:
  Mining Publications
• Subseries:
  Open File Report
• Document Type:
  Text
• Genre:
  Conference Publications ; Final Contract Report
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PRC - Pittsburgh Research Center
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-175
• NIOSHTIC Number:
  nn:10001407
• NTIS Accession Number:
  PB-273292
• Citation:
  NTIS: PB 273 292 Available for Reference At Bureau Libraries; :1-175
• Federal Fiscal Year:
  1977
• Performing Organization:
  A. D. Little, Inc.
• Peer Reviewed:
  False
• Source Full Name:
  NTIS: PB 273 292 Available for Reference At Bureau Libraries
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:4b44a96b56bf3412c8671f4820be564dd01703eafed0e52606f00978eb36e9e6edec3ff1a9797dfddcfc26aefe7f504de9d6535b637fd3fe1ff7c748e1c549ac
• Download URL:
  https://stacks.cdc.gov/view/cdc/234984/cdc_234984_DS1.pdf
• File Type:
  [PDF - 6.33 MB ]