Magnetic field strength mapping of the Helvetia Coal Co. Lucerne No. 8 Mine at medium frequency
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.

Search our Collections & Repository

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields

Language:

Dates

Publication Date Range:

to

Document Data

Title:

Document Type:

Library

Collection:

Series:

People

Author:

Help
Clear All

Query Builder

Query box

Help
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Magnetic field strength mapping of the Helvetia Coal Co. Lucerne No. 8 Mine at medium frequency

Filetype[PDF-568.15 KB]


  • English
    • Details You May Also Like

    Details:

    • Personal Author:
      Cory, Terry S.
    • Corporate Authors:
      United States. Bureau of Mines.
    • Description:
      "This report describes magnetic field measurements in the Helvetia Coal Co. Lucerne No. 8 Mine for purposes of deriving a mapping of the magnetic field strength covering the major haulageways which contain conductors. The results of the testing at medium frequency show that coverage of the entire mine area containing conductors can be achieved employing wireless radio techniques whereby radio signals are coupled into and are carried by these conductors. These results confirm earlier qualitative testing of the Collins Mine Wireless Radios in this mine. These results, performed over the frequency range 71-2890 kHz, illustrate the effect of frequency on the radio propagation with the conclusion that the best overall coverage is obtained at frequencies approximating 1000 kHz. This report presents all the raw data and the reduced data in the form of magnetic field strength contour maps. Sufficient information is provided to enable independent reduction of the data. A summary of observations which can be made directly from the contour maps is given." - NIOSHTIC-2

      NIOSH no. 20030898

    • Subject:
    • Document Type:
      Report
    • Funding:
      U.S. Bureau of Mines purchase orde. P0372716
    • Collection(s):
      National Institute for Occupational Safety and Health
    • Main Document Checksum:
    • File Type:

    Supporting Files

    • No Additional Files

    More +

    You May Also Like

    Checkout today's featured content at stacks.cdc.gov