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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Addressing recommended replacement of certain components in Harmon Industries' "Electro Code 4"' and "Electro Code 4 Plus" intermediate signal units

Document Series
Safety Advisories
Safety Advisory Number
Subject Signal and Train Control
Signal and Train Control; symmetry distortion ; signal lighting ;
sa2000_02.pdf (8.73 KB)

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Effective Date: Thursday, May 25, 2000