Nice photos..... I knew I had seen them before. It was kind of fun having a D&RGW unit on the point. Many had the real Mars light on the nose, and it went in a figure eight. There were a few SP units that had two seal beam lights in place of the Mars. They would each flash back and forth and were set at 45 degree angles. Paul McGuffin
Those sound like Oscitrols, aka "The Poor Man's Gyralite".:tb-biggrin: Oscitrol Lights - Gyrating Warning Lights SP Oscitrols I know some B36-7s, the 7200-series GP40-2s built in 1984, and a handful of SP's 7500-series SD45 rebuilds had them. Never got to see one operate; offhand, do you remember how quickly they flashed back and forth?
You're correct, the 7200's and a few SD45s. As a matter of fact, a few, and I do mean very few, SD45's had a yellow "gumball" light. This was back in the mid 1970s. As far as the flash sequence; I would say just under one second for the two lights, about like the ditch lights we have now. Paul McGuffin
WOW! Look what showed up on Ebay Paul Mc Guffin Gyralite off of a Southern Pacific locomotive - eBay (item 320258252447 end time Jun-06-08 16:29:57 PDT)