I'm building a pretty substantial layout using about 30 atlas switches. Most of them are old, taken from a layout I built in the 90's. All of the switches worked fine back then. The problem I'm having is with the rails not conducting electricity. I'm testing for continuity across the points and on about half of the switches, there is no continuity. Somewhere there is a break in the line right around the switch points. I've found this in about half of my switches. Is this possible? Am I doing something wrong? Some work, some don't....very odd.