By late 1964 ALCO had determined that an extra 100-hp did make a difference to some customers, and the 2,500-hp C425 model was the result. Improvements over the C424 included a higher capacity main generator, a simplified electrical control system, increased radiator capacity and an upgraded 251C prime mover. The appearance of the body was nearly identical to the C424, with one major exception being the addition of a bulge above the radiator intake grille at the rear of the long hood. A total of 90 units were produced between late 1964 and 1966, all for US roads. The largest purchases were made by Pennsylvania and Spokane Portland & Seattle.
- C425 Phase 2 models include cab with either horizontal or vertical headlights per the prototype
- Models include redesigned ?AAR? style truck sideframes with separate brake cylinders and separate bearing cap detail (included when appropriate per the prototype).
- Directional lighting w/ golden-white LEDs
- Five-pole skewed armature motor with dual flywheels for optimum performance at all speeds
- Factory-equipped with AccuMate� knuckle couplers
- Analog version features NMRA 8 pin plug for DCC
- Separately-applied wire grab irons, ladders, and drop steps
- Separately-applied marker lenses
- Improved painting and printing w/painted handrails
- Two painted crew members
New Sound Features for Gold Series:
- Supports all DCC-programming modes
- Flexible mapping of function keys F0 to F28.
- A total of six DCC function outputs are available
- Follows all NMRA DCC standards and recommended practices.
Analog (DC) Operation
- The LokSound Select Dual-Mode decoder allows your Atlas Gold Series locomotive to be used on DC as well as on DCC layouts.
- Please note that the Atlas Quantum Engineer will NOT operate an Atlas Gold Series locomotive equipped with a LokSound Select decoder on an analog (DC) layout. However, the sound and lighting functions of the LokSound Select decoder in the Atlas Gold Series C424/425 locomotive can be controlled by an easy-to-use basic DCC system
- Also note that on a DC-powered layout, a DCC and sound equipped locomotive (such as the Atlas Gold Series C424/425) CANNOT be consisted with another locomotive that does not also have both DCC and sound. (This statement does NOT apply to DCC-equipped locomotives operating on a DCC layout.)
- Over 20 sound effects are available, including engine start-up and shutdown, prime mover sounds through all eight notches, bell, air horn, air compressor, dynamic brakes and more.
- There are 16 user-selectable horns, 2 user-selectable bells, and 2 user-selectable synchronized brake squeals.
- Manual and Automatic Notching modes with the ability to change modes ?on the fly? are provided for true realism.