Train Control Systems IMF4 N-scale decoder for InterMountain F-units

$48.95 $45.90


The IMF4 is a N-scale drop-in decoder which is designed for InterMountain F-unit locomotives. Examples include the following:


  • F3A/B
  • F7A/B
  • F9B

See the installation pages for a full list of compatible engines!

NOTE: This version of the IMF4 is designed for the older style InterMountain frame where the motor is connected to the control board via brass motor feet.

  • Back EMF Load Compensation:

Provides superior slow speed control and high performance under load.

  • Quiet Drive:

Super-quiet motor control for “buzz” free motor performance.

  • DC Mode:

Decoder will automatically detect DC power. You can also configure how your lighting effects function on DC.

  • RailCom®:

This feature allows the decoder to talk to the command station. RailCom supports expansion for new features.

  • Variable Momentum:

Allows you to make custom acceleration and deceleration curves.

  • LED Support:

This product does not require external resistors when connecting LED’s.

  • Incandescent Bulb Support:

This decoder can be used with 12 Volt bulbs.

  • Function Remapping:

Buttons 0 through 12 may be used to control the lighting functions of this decoder.

  • Programmable Lighting Effects:

Choose from 20 separate user-programmable lighting effects!

  • Dimmable Brightness:

Configure multiple different brightness levels for your LED’s or incandescent bulbs.

  • Decoder Lock:

Feature which prevents accidental/unwanted programming while activated.

  • Airwire™ Compatible:

Fully compatible with Airwire™ operation.

  • User-Loadable Speed Tables:

Configure custom speed curves and set speed limits.



Interface Type: Drop-In

Dimensions (L x W x H): 2.158″ x 0.47″ x 0.179″ or 54.81mm x 11.93mm x 4.54mm

Scale: N Scale

Continuous/Peak: 1.0/2.0 Amp

Total Functions: 3

Function Rating: 80 mA

12V Outputs: 4

LED Outputs: 4



Decoder Literature:  IMF4.pdf

Comprehensive Guide:  Comprehensive-Programming-Guide.pdf