Sherman, Set the Wayback machine to 1967

Sherman– 1967 Please.

This KarTrak railroad label is probably one of the oldest items in our collection.  The labels were hand-made by attaching strips of red, white and blue reflective material to a piece of 14 gauge sheet steel.  They were all 10 digits long.  Four digits identified the railroad and six identified the car. Each tag cost about $15 to make.

Our Kartrak Tag

The Automatic Car Identification (ACI) system was originally developed by GTE in 1961 and implemented by Dave Collins in 1967.  Dave later went on to form Computer Identics Corp. in Westwood and Canton, MA.

Original 1967 Ad for the Rail Scanning System.

The labels were read by moving beam scanners that were activated by a wheel sensor as the car moved by.  The scanner was mounted along the side of the track in a large metal NEMA enclosure with a hooded window.  It used a Xenon bulb and a four-sided spinning mirror along with a camera-like lens to read the tags.  The decoder used some circuitry to decode the red, white and blue channels from the signal that was reflected back from the tag.  If I remember correctly, the last time I saw one of these a PDP-11 series mini-computer ran the software system for the scanner.

The major problem with the system was dirt. When the labels got dirty they did not read well. The railroads would not clean them and this caused the system to be discontinued in 1974.

The last time I can recall these systems being used or seeing a label in public was in the Washington DC Metro system in the mid 1980’s. Computer Identics Corp. was still maintaining them at this time.

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