Southern Digital


PR4 Digitrax PC Interface


Using the PR4 Programmer and SoundLoader software:

The PR4 lets SoundFX users download new project sound files and even refresh the sound decoder’s firmware for the latest updates.

The PR4 makes decoder programming and interfacing your layout and computer easier than ever. The PR4 seamlessly switches between computer interface and decoder programming modes automatically without having to press any buttons. The PR4 is electrically isolated between USB and LocoNet for added stability and protection. Packaged in a smaller footprint the PR4 offers all the same great features as the PR3 it replaces.

It also acts as a computer interface and LocoNet Translator for your PC

  • You can substitute different .wav files into a sound project file (.spj) or you can start from scratch and build your own sound project.
  • You can download sound projects from the Digitrax Sound Depot web site
  • You can upload sound projects you have created to share with others, too!
  • We encourage sound project file sharing among hobbyists.
  • You can download a sound project into your Digitrax SoundFX decoder equipped locomotive.
  • You can try out sound projects downloaded to your locomotives on the programming track without having to run it around the layout.

Available on backorder

PR4 Features

  • Multifunction USB to LocoNet connectivity for your railroad.
  • Optimized for Direct mode, up to 3 times faster than PR3.
  • Electrically Isolated between USB and LocoNet.
  • Digitrax “SoundLoader” compatible. Programs Digitrax sound projects to SFX decoders.
  • Programs CV’s for most DCC decoders.
  • LocoNet MS100 mode with Fully Buffered Input and Output data.
  • Runs on most Operating systems.
  • Automatic configuration. No jumpers or switches required.
  • Standalone operation for CV and SoundFX programming without needing a Digitrax Command Station.
  • LED state indicator lights.
  • Small, convenient package.
  • Firmware updates available from Digitrax Web site.
  • Includes PS14 Power Supply


Digitrax PR4 Programmer comes with:

  • PR4 Programmer
  • Download SoundLoader Software
  • USB Cable needed to hook up your PC’s USB port.
  • PS-14 Power Supply

In addition, you’ll need:

  • A Computer running Windows/MAC OS with SoundLoader or equivalent program running
  • An isolated programming track section (You won’t need a “power booster” to increase programming track voltage.)
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