I suppose this interest of mine started back around 1971 or 1972 when I was walking along the Main Line of the Reading Railroad near my home in Reading, PA.  I was amazed at the colors displayed by these huge signals and tried to understand what they meant and why they were there.  Because  of my  childhood tendency to rip everything apart I put my hands on at home to see what made it work, I was very eager to see how these railroad signals worked, and over the last 20 plus years I was very fortunate to learn many things about railroad signaling.