Marx 454 Automatic Block Signal

[trainsintheattic]

Wow!  Super info and I very much appreciate your wisdom. Thanks, I'm on my way to the basement now to work on it. Best!

[lionelsoni]

You can operate the signal directly from the track, using an insulated length of one outside rail, called a "control rail".

The modification to the signal is simple:  Disconnect everything from the lamps.  If the lamp socket shells are already connected together as part of the structure (or are part of the structure), leave them that way.  If not, connect them together.  Then connect this point to the control rail.  Connect the other terminal of the green lamp's socket to the outside rails other than the control rail.  Connect the other terminal of the red lamp's socket to the center rail, or to an accessory voltage if you like.  Finally, connect two of whatever lamp type is in the signal in parallel with the red lamp.  You can instead use one lamp of a type that draws about twice the current of the signal lamps.  Hide this lamp (inside the signal box?).

The red lamp is on and the green lamp is off when the train is on the control rail.  Otherwise, both lamps are lit dimly in series.  So the extra lamp wired in parallel with the red lamp drops its voltage almost to nothing, dimming it out and brightening the green.  This circuit was described at least 70 years ago by Albert Kalmbach (of Kalmbach Publishing fame), but using a resistor.  A lamp works better, because, when the signal is red, it draws much less current than a suitable resistor does.

[sir james I]

As kids playing on the floor stopping the train with a signal was fun. As for automatic red to green you need a train detector, Lionel and MTH make them, follow the wire directions that come with it.

The detector will cost you much more than the signal did.

[trainsintheattic]

I was gifted with this unit the other day and in very nice condition. I'm rather new to the hobby and wiring skills are pretty basic. Have tested as instructed and it works fine. Two questions: FIRST, why would I want to do this? Why stop a train then have to get up and start it rolling again by flipping the switch on the Marx block signal? Am I missing something? What is the point in that? Up and down and up and down...I don't get it? SECOND, what I'd rather have it do is just change colors --- as the train goes by, red goes to green or green goes to red...and that's it. I'm into appearances, not function. If the lights just change as the train goes by --- and the train does NOT stop --- then I'd be delighted!  Is there a way to wire this Marx unit so that ONLY light change occurs, not train halting? A brief explanation of the wiring scheme would be great. Thanks so much!