To set to booster only mode:
1. Move the small switch on the bottom toward the rear of the box.
2. Connect a Power Cab or Pro Cab directly to the front of the SB3, SB3a, or SB5 smart booster in a cab bus jack.
3. On your cab, Press <PROG/ESC> followed by <5> to see the SET CMD STATION prompt on the LCD of the cab.
4. Press <ENTER> repeatedly until you see “ENABLE BOOSTER.”
*** Note, if you are missing this part of the menu in your booster, contact NCE for the latest firmware version, 1.65B, free of charge.
5. Press <1> to enable booster only mode
The status LED on the booster should start flashing rapidly, indicating no command station control bus signal is present. The Smart Booster is now in "Booster Only" mode. Use the “Control Bus” jack on the front of the booster. Connect your DCC signal here. To return the booster to normal command station mode, reverse the above process. (switch toward the front of the box, and disable booster mode in SET CMD STATION).