U25C

Information on this wiki page provides particular details about this model not found in our basic guide.

U25C
Model Information Manufacturer Korea Brass Scale HO-Scale Power Type DCC Dual Mode w/Sound Release Date 2025 Retail Price $249.95 Decoder Information Decoder Type(?) WOW101-Diesel Version(?) 4.5 Lighting Functions 6 Prototype Information Builder GE Transportation Systems Build Date September 1963 - December 1965 Motive Power Diesel Cylinder Cfg 16 Power Output 2,500 hp (1,860 kW) More Info [1]

Overview

TCS Locomotive Works DCC sound-equipped U25C includes a TCS WOWSound® decoder with factory-preset prototypical sound configuration. This model also includes Keep-Alive® for uninterrupted operation, even over dirty track. The WOWSound® Diesel locomotive sound package includes sounds for horn, bell, prime mover, air compressor, cooling fan, coupler close/release, brakes, and many more! (See below)

Specific Features

Features include:

• DCC sound-equipped for sound, speed, direction, and lighting control
• Dual-mode NMRA-compliant decoder operates sound, motor, and lights on DCC or DC power.
• TCS true CD-quality audio (16-bit, 44,100Hz)
• Authentic and prototypical sounds set by default
• Over 50 horn and over 40 bell options
• Keep-Alive® included, which keeps your engine running during power interruptions due to dirty track or loss of electrical contact
• Directional headlights enabled by default
• TCS' industry-leading "quiet drive" Back EMF motor control for superior slow-speed performance and load compensation
• User-loadable speed table options (3-point, 28-point, and 126-point curves)
• Two select-able Throttle Modes
• Two configurable Momentum Modes
• Die-cast frame

Additional Features

The U25C is at its heart a WOWDiesel decoder but has had some customization to make it specific to the locomotive. The information below details where CV’s and operation differ from the standard Steam decoder.

Note: This WOWSound® product includes TCS' Audio Assist® auditory feedback program.

Button Mappings

The values outlined below in the button mapping, sound list, and CV values are the defaults assigned to this particular decoder from the factory.

For information on how to program your locomotive using the values provided in the charts below, please see our List of Standard CVs, and/or List of Indexed CVs for WOWDiesel Version 4.

Button Mappings
Function Button	Sound Action	Light Action	Dual Enabled
0	None	Lamp 0F / 0R (Directional)	True
1	Bell	Cab/Marker Lights	False
2	Playable Horn	Marker Lights	False
3	Short Horn Blast	Constant Bright - Both Directions - Lamp 3	False
4	Grade Crossing Quill	Constant Bright - Both Directions - Lamp 4	False
5	Dynamic Brakes	Constant Bright - Both Directions - Lamp 5	False
6	Brake Release	Constant Bright - Both Directions - Lamp 6	False
7	Train Brake (apply)		False
8	1x Press Mute/Unmute 2x Press to rotate page 4x Press enter Audio Assist		True
9	Rotate		False
10	Manual Notch Up		False
11	Manual Notch Down		False
12	Prime Mover Ignition		False
13	Coupling		False
14	Uncoupling		False
15	Momentum Mode Selection		False
16	Crew Alert On/Off		False
17	Windshield Wipers On/Off		False
18	Air Spit		False
19-28	None		False

Random Sound Mapping
Random Sound Number	Sound Type	Specific Sound
1	Air Compressor	(Automatic With Prime Mover Selection)
2	Air Spitter
3	Disabled	None
4	Disabled	None

Sound List

Please refer to the WOWDiesel Version 4.5 Sound List for a complete list of sounds included on this decoder.

CV Addendum (Standard CV's)

The U25C follows the motor and lighting CV's as described in in TCS' Comprehensive Programming Guide and List of Standard CV's.

CV Addendum (Indexed CV's)

The U25C decoder follows the motor and lighting CV's as described in TCS's WOWDiesel Programming Guide. Listed below are the TCS Indexed CV's for the U25C decoder:

Sound CV's

The table below lists all of the Indexed CV's used to configure "sound-related features" of the decoder. To use the information in this table, first program CV 201 with a value of 4, CV 202 with the value shown in the first column, and then use CV 203 and CV 204 to change the configuration.

Sound CV's (CV 201 = 4)

Indexed CV (CV202)	Indexed CV Value (CV203,CV204)	Description
8	0,7	Horn Type Selection (Southern Pacific #3100)
10	0,80	Master Volume
11	0,17	Prime Mover Selection (GE 7FDL16 (Type 1))
23	0,15	Bell Type Selection (Southern Pacific U25B #3100)