The Form 400 Powerpack was introduced in 1957 by GE which had a much bigger slipfitter to include the ballast and photocontrol rectanple. The Form 400 Powerpack also had a little brother, called the Form 175 Powerpack shown here. It was orginally a 175 watt mercury, later converted by the utility to 100 watt HPS. I changed it back to 175 watt mercury shortly after acquiring it. It sure looks much better when lit in mercury than the sickly glow of HPS! Anyway enjoy the pics!
The clear BT-28 lamp inside is a Westinghouse 175 watt, likely from the late 1970s. The refractor looks nice with a clear lamp, at least to me!
The ballast inside is just a simple HX ballast that came out of a yard light. But at least it allows a mercury lamp to be run in the lumianire. You can see the sticker still intact and readable, since the late 1950s!
