May 20, 1935, after the electrification of freight lines in New Jersey and Washington,DC. Extensions to Potomac Yard across the Potomac River from Washington, as well as several freight branches along the way, were electrified in 1937 and 1938. The Potomac Yard retained its electrification until 1981. Re-signaling In the 1930s, PRR equipped the New York–Washington line with Pulse code cab signaling. Between 1998 and 2003, this system was overlaid with an Alstom Advanced Civil Speed Enforcement System (ACSES), using track-mounted transponders similar to the Balises of the modern European Train Control System. The ACSES will enable Amtrak to implement positive train control to comply with the Rail Safety Improvement Act of 2008. Founding and operation of Amtrak Reorganization and bankruptcy In December 1967, the UAC TurboTrain set a speed record for a production train: between New Brunswick and Trenton, New Jersey. In February 1968, PRR merged with its rival New York Central Railroad to form the Penn Central (PC). Penn Central was required to absorb the New Haven in 1969 as a condition of the merger. On September 21, 1970, all New York–Boston trains except the Turboservice were rerouted into Penn Station from Grand Central; the Turboservice moved on February 1, 1971, for cross-platform transfers to the Metroliners. In 1971, Amtrak began operations, and various state governments took control of portions of the NEC for their commuter transportation authorities. In January, the State of Massachusetts bought the Attleboro/Stoughton Line in Massachusetts, later operated by the Massachusetts Bay Transportation Authority. The same month, the New York State Metropolitan Transportation Authority bought, and Connecticut leased, from Penn Central their sections of the New Haven Line, between Woodlawn, Bronx, New York and New Haven, Connecticut. In 1973, the Regional Rail Reorganization Act opened the way for Amtrak to buy sections of the NEC not already been sold to these commuter transportation authorities. These purchases by Amtrak were controversial at the time, and the Department of Transportation blocked the transaction and withheld purchase funds for several months until Amtrak granted it control over reconstruction of the corridor. In February 1975, the Preliminary System Plan for Conrail proposed to stop running freight trains on the NEC between Groton, Connecticut, and Hillsgrove, Rhode Island, but this clause was rejected the following month by the U.S. Railway Association. By April 1976, Amtrak owned the entire NEC except Boston to the RI state line, which is owned