Challenger UP #3985
Union Pacific 3985
Power type: Steam
Builder: American Locomotive Company(ALCO)
Serial number: 70174
Build date: July 1943
Configuration: 4-6-6-4
UIC classification: (2'C)C2' h4
Gauge: 4 ft 8 1/2 in (1,435 mm)
Driver diameter: 69 in (1,753 mm)
Weight on drivers: 404,000 lb (183.3 tonnes)
Locomotive & tender combined weight: 1,073,900 lb (487.1 tonnes)
Boiler pressure: 280 lbf/in² (1.93 MPa)
Cylinders: Four
Cylinder size: 21 in × 32 in (533 mm × 813 mm)
Tractive effort: 97,350 lbf (433.03 kN)
Career: Union Pacific Railroad
Class: 4664-4
Number in class: 11 of 25
Number: UP 3967, UP 3718, UP 3985
Nicknames:"Challenger"
Retired: 1962
Restored: 1981
Disposition: Operates in occasional excursion service
Sound Projects
Digitrax Challenger UP #3985 Sound scheme Copright (c) Digitrax Inc. July 8th 2007
Courtesy of Union Pacific Steam Program
UP 3985 Challenger
(C) General Notes
This sound recording courtesy of Union Pacific Heritage Steam Programme. Visit arranged by Larry Hodson. All sounds recorded by AJ Ireland at Dunsmuir CA and Klamath Falls OR in 2005.
Each engine we have recorded has a distinct 'personality', so a particular locomotive example may sound slightly different due to unique e.g. tappet, crank-rate shell vibrations and exhaust-stack, chuff differences. Horns and bells are often moved between locomotives, and some roads may change/upgrade prime-movers, or change a normally aspirated engine with turbo-chargers etc.
This sound recording courtesy of Union Pacific Heritage Steam Programme. Visit arranged by Larry Hodson. All sounds recorded by AJ Ireland at Dunsmuir CA and Klamath Falls OR in 2005.
This project takes the EM-1 and SP AC-9 projects together to create an Oil burning version of the articulated sounds where cylinder 2 is in voice 2 and cylinder 1 plays in voice 1.
This makes it possible for the two cylinder sounds to fall out of sync and sound more real.
The whistle was replaced from the original Digitrax Challenger WAV files. As well the burner, dynamo and air pump was taken from another recording of the loco during an excursion. The whistle has lots more ambient effects.
SoundLoader Software
Using your PR3 programmer and SoundLoader Software, it’s quick and easy to download sound project files into your Digitrax FX decoders.
Format Information
With Digitrax Sound FX decoders and downloadable sound project files (.spj), you can download your choice of sound schemes into any Sound FX equipped locomotive. You can use spj’s that are available for free, you can modify those schemes or you can create your own!
Sound Decoders
Digitrax offers a wide variety of Sound FX decoders to fit many different locomotives. You’ll need to have a Digitrax SFX decoder installed to take advantage of using .spj files.
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