Atlas - 4507 - Locomotive, Diesel, EMD SD7 - Baltimore & Ohio - 764

Model Information: The model was introduced in 1990 and the early releases were made by Kato Japan for Atlas. From 2004 on, the models were made in China and the internals were modified to a more modern mechanism. The Atlas SD7, SD9, SD24 and SD26 all share the same internal mechanism and differ only in their shell details. The modern releases fall under the "Classic" label for the SD7 and SD9 models and "Master" label for the SD24 and SD 26.

The early releases featured the Kato-designed "low friction drive" which had been successfully used in their Kato-branded U30C model. This design allowed clean transfer of current from wheels to long copper strips to the chassis and then to the lightboard. This may not sound innovative, as many modern mechanisms use this design today, but in 1990 it was a game-changer. The post-2004 releases are fairly standard "modern" mechanisms featuring a split-frame, dual-flywheels, and body-mounted magnetic operating knuckle couplers. They run quiet and smooth and can pull 30 or more standard-weight cars.

DCC Information: Models produced from 2006 are DCC Ready or Dual-Model Decoder Equipped. They accept the following drop-in decoders:
- Digitrax DN163A0: 1 Amp N Scale Mobile Decoder for Atlas N-Scale GP40-2, U25B, SD35, Trainmaster, B23-7 and others
- TCS AMD4 (Installation for Atlas SD-9)
- NCE N12A0: Plug and play decoder for N-Scale Atlas GP40-2, U25B, U23B, B23-7, 30-7, 36-7, GP38, SD25, TRAINMASTER, etc.
- MRC 1812: N-Scale Sound Decoder for most Atlas short/medium locos (selection of 4 prime movers - might not be prototypical for this model however)

Earlier DCC factory-equipped versions were fitted with Lenz LE063XF decoders, whereas most recent versions are fitted with NCE N12A0 decoders. The Atlas version of these decoders will respond to manufacturer's address "127" (CV8) i.e. "Atlas Model Railroad Products", though being identical to their original manufacturer's specification.

Prototype History: An SD7 is a 6-axle road switcher diesel-electric locomotive built by General Motors Electro-Motive Division between February 1952 and November 1953. It had an EMD 567B 16-cylinder engine producing 1,500 horsepower (1.12 MW) for its six traction motors. 188 were built for United States railroads. Starting in August 1953 a total of 26 SD7s were produced which used either the 567BC engine or the 567C engine. These units are noted on the roster below.

This was the first model in EMD's SD (Special Duty) series of locomotives, a lengthened B-B GP7 with a C-C truck arrangement. The two extra axles and traction motors are useful in heavy, low speed freight service. SD series locomotives are still being produced today, with the SD70 being the most popular example in current production, and with many SD40-2s and rebuilds to SD40-2 specifications, or SD60s still in operation.

Yesterday's Special Duty eventually became today's Standard Duty, and yesterday's General Purpose has become today's Special Purpose ("time" freight and other time-sensitive lading). True GPs were discontinued after the completion of the last GP60 in 1994. Recently intermodal and other fast freights may be hauled by 6 axles locomotives with 4 powered axles, such as the SD70Ace-P4.

Many earlier model GPs, most particularly GP40s, GP39s and GP38s, also their SD equivalents, SD40s, SD39s and SD38s have been rebuilt to Dash 2 standards for another 30 to 40 years of service.

From Wikipedia

Road Name History: The Baltimore and Ohio Railroad (reporting marks B&O, BO) is one of the oldest railroads in the United States and the first common carrier railroad. It came into being mostly because the city of Baltimore wanted to compete with the newly constructed Erie Canal (which served New York City) and another canal being proposed by Pennsylvania, which would have connected Philadelphia and Pittsburgh. At first this railroad was located entirely in the state of Maryland with an original line from the port of Baltimore west to Sandy Hook. At this point to continue westward, it had to cross into Virginia (now West Virginia) over the Potomac River, adjacent to the confluence of the Potomac and Shenandoah rivers. From there it passed through Virginia from Harpers Ferry to a point just west of the junction of Patterson Creek and the North Branch Potomac River where it crossed back into Maryland to reach Cumberland. From there it was extended to the Ohio River at Wheeling and a few years later also to Parkersburg, West Virginia.

It is now part of the CSX Transportation (CSX) network, and includes the oldest operational railroad bridge in the USA. The B&O also included the Leiper Railroad, the first permanent horse-drawn railroad in the U.S. In later years, B&O advertising carried the motto: "Linking 13 Great States with the Nation." Part of the B&O Railroad's immortality has come from being one of the four featured railroads on the U.S. version of the board game Monopoly, but it is the only railroad on the board which did not serve Atlantic City, New Jersey, directly.

When CSX established the B&O Railroad Museum as a separate entity from the corporation, some of the former B&O Mount Clare Shops in Baltimore, including the Mt. Clare roundhouse, were donated to the museum while the rest of the property was sold. The B&O Warehouse at the Camden Yards rail junction in Baltimore now dominates the view over the right-field wall at the Baltimore Orioles' current home, Oriole Park at Camden Yards.

At the end of 1970 B&O operated 5552 miles of road and 10449 miles of track, not including the Staten Island Rapid Transit (SIRT) or the Reading and its subsidiaries.

Read more on Wikipedia.

Brand/Importer Information: In 1924 Stephan Schaffan, Sr. founded the Atlas Tool Company in Newark, New Jersey. In 1933 his son, Stephan Schaffan, Jr., came to work for his father at the age of sixteen. Steve Jr. built model airplanes as a hobby and frequented a local hobby shop. Being an enterprising young man, he would often ask the owner if there was anything he could do to earn some extra spending money. Tired of listening to his requests, the hobby-store owner threw some model railroad track parts his way and said, "Here, see if you can improve on this".

In those days, railroad modelers had to assemble and build everything from scratch. Steve Jr. created a "switch kit" which sold so well, that the entire family worked on them in the basement at night, while doing business as usual in the machine shop during the day.

Subsequently, Steve Jr. engineered the stapling of rail to fiber track, along with inventing the first practical rail joiner and pre-assembled turnouts and flexible track. All of these products, and more, helped to popularize model railroading and assisted in the creation of a mass-market hobby. The budding entrepreneur quickly outgrew the limitations of a basement and small garage operation. Realizing they could actually make a living selling track and related products, Steve and his father had the first factory built in Hillside, New Jersey at 413 Florence Avenue in 1947. On September 30, 1949, the Atlas Tool Company was officially incorporated as a New Jersey company.

In 1985, Steve was honored posthumously for his inventions by the Model Railroad Industry Association and was inducted into the Model Railroad Industry Hall of Fame in Baltimore, Maryland. In addition, Steve was nominated and entered into the National Model Railroad Association Pioneers of Model Railroading in 1995.

In the early 1990s, the Atlas Tool Company changed its name to Atlas Model Railroad Company, Inc.