WANTED: NEW STANDARDS FOR AFO

With the advent of AFO track circuits many problems have been presented since impedance is the primary attenuating factor, not resistance. With a given shunt, the resistance will remain constant, but as the audio frequency goes up, the impedance goes up, thus less attenuation. If the standard .06 ohm shunt is used for aligning AFO track circuits, the impedance is affected by frequency, track conditions and ballast conditions. This spring General Railway Signal Co. will start an extensive project to compile the information needed for developing new standards and new equipment which will make the alignment of AFO track circuits more accurate.

• Corporate Authors:

  Simmons-Boardman Publishing Corporation

  P.O. Box 350
  Bristol, CT  United States  06010

  Simmons-Boardman Publishing Corporation

  508 Birch Street
  Bristol, CT  United States  06010
• Publication Date: 1974-4

Media Info

• Features: Figures;
• Pagination: 8 p.
• Serial:
  • Railway System Controls
  • Volume: 5
  • Issue Number: 4
  • Publisher: Business Press International Limited

Subject/Index Terms

• TRT Terms: Signaling; Track circuits
• Old TRIS Terms: Audio frequency track circuits
• Subject Areas: Operations and Traffic Management; Railroads;

Filing Info

• Accession Number: 00054306
• Record Type: Publication
• Source Agency: Railway System Controls
• Files: TRIS
• Created Date: Jun 10 1976 12:00AM