A model railroad remote object comprises a proximity detector, an on-board accessory, and an on-board processor. The proximity detector changes state based on proximity of the detector to a proximity source. The accessory, which is located on or within the remote object, exhibits a behavior based on a parameter. The processor, which is operatively connected to the proximity detector and the accessory, affects the value of the parameter of the accessory based on the state of the proximity detector. By way of illustration and not limitation, the on-board accessory may be an audio device, the behavior may be emission of sound, and the parameter may be sound volume.