. "railroad use" . . . . . . "Amtrak's 25 Hz traction power system" . . . "electric traction system" . "12 kV, 25 Hz AC" . "Southend Electrification" . "owned and operated by Amtrak" . "electrification" . . "12 kV AC at 25 Hz" . "Amtrak power system" . "alternating current" . "12 kV at 25 Hz" . . . "11 kV 25 Hz AC" . "Amtrak's 25 Hz traction power system" . "25Hz AC" . "12,000 volt 25 hertz AC" . "12 kV, 25 Hz" . "Amtrak's Lamokin converter station" . "replaced" . "11 kV AC, 25 Hz" . "Amtrak's 25 Hz traction power system#Conestoga to Atglen transmission line" . "Amtrak" . "11 kV overhead catenary system" . . "25 Hz traction power" . . "25 Hz traction power system" . "11 kV 25 Hz AC" .