EMD F-units were a line of diesel-electric locomotives produced between November 1939 and November 1960 by General Motors Electro-Motive Division and General Motors-Diesel Division. Structurally, the locomotive was a carbody unit, with the body as the main load-bearing structure, designed like a bridge truss and covered with cosmetic panels. The so-called bulldog nose was a distinguishing feature of the locomotive's appearance, and made a lasting impression in the mind of the traveling public.
The F-units were the most successful "first generation" road (main line) diesel locomotives in North America, and were largely responsible for superseding steam locomotives in road freight service. Before this, diesel units were mostly only built as switcher locomotives, and only used in rail yards.
F-units were sometimes known as "covered wagons", due to the similarity in appearance of the roof of an F-unit to the canvas roof of a Conestoga wagon, an animal-drawn wagon used in the westward expansion of the United States during the late 18th and 19th centuries. When a train's locomotive consist included only F-units, the train would then be called a wagon train. These two usages are still popular with the railfan community.
MILW F7A-UNITS FEATURES:
Dual single-chime horns
Rear roof corner grab
Emergency "Big Hole" light; activated when E-stop button is pressed on DCC+Sound version only
All units are powered
Factory installed SoundTraxx Tsunami2 sound and DCC decoder (DCC+sound units only)
DCC+Sound models are "dual mode" and will operate under both DCC and DC
Directional constant lighting; headlight brightness remains constant
On DCC-ready B-units, back-up lights or marker lights (if equipped) will come with LEDS, but wires will not be connected to the circuit board
Scaled from prototype resources including drawings, field measurements, photographs, and more
Fully-assembled and ready-to-run
Accurately-painted and printed paint schemes
Separately applied photo etched metal and injection molded detail parts
Coupler cut levers
Wire grab irons
Detailed fuel tank with fuel fillers, fuel gauges, breather pipes, and retention tanks
Body mounted McHenry scale knuckle couplers - Kadee compatible
DCC-ready Non-sound version features 21-pin NEM DCC plug
Genesis driveline with 5-pole skew wound motor, precision machined flywheels, and multi-link drivetrain for trouble free operation
All-wheel drive with precision gears for smooth and quiet operation
All-wheel electrical pickup provides reliable current flow
Wheels with RP25 contours operate on all popular brands of track
LEDs for realistic appearance
Heavy die-cast frame for greater traction and more pulling power
Minimum radius: 18"