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12V Signals in a 9V setup

The conversion
Converting the 12V signal for use with the 9V track is really easy. However if you have never seen the 12V signal but you are interested to get one, this page might be very informative. For most people a lot of stuff on this page is probably not required; a simple schematic and a picture would suffice. My personal policy is better too much information than too little.
Oh, and a little disclaimer here: do this at your own risk...
Required materials
7860 Remote Controlled Signal (12V)
5305 Extra rail connection wire (9V)
4548 Extra speed regulator (9V) OR 7864 Transformer (12V)
Note: the extra transformer/speed regulator is for powering the signal lights independant of your train setup. It is also possible to power this from your existing power supply but lights dim as the trains slow down or stop. For a better effect power the lights independantly.

Wires
The 12V electrical wires have different connectors than the 9V connector plates. There is at least one conversion required to create a working model. I used the 12V transformer to power the light (and the lights in my city), if you don't have a 12V powersupply but you do have a spare 9V speed regulator; you will need another converter to power the control box. Do not worry, all te required parts for the conversion are in the signal set itself.
Take a look at the pictures to see how the conversion is done.


	The control box with the 12<>9 connector. Click the picture for a bigger version (sorry, the picture is a little fuzzy)

Signal light
The light doesn't require any modification, even the wires for this part don't require modification since the light is connected to the control box and they both have the 12V connections.
The light simply turns red or green dependant on the polarity of the current.


	The signals post can keep it's 12V connections

Track
The signal works as a switch, putting power on a piece of isolated track. If you examine the 12V conductorpieces you will notice a little piece of plastic interrupts one side, this is how a part of the track is isolated. To create the isolated track cut the metal on the place indicated. The picture indicates where to apply the cut. You will need two of those pieces.


	The track is cut on one side. Click picture for a better view

Control Box
The control box doesn't require any modification. Instead I'll explain what it does. The control box has two outputs that depend on which button is pressed.
Green button is pressed

Output #1 connect both wires (ie. shortcircuit)
Output #2 reverse polarity

Red button is pressed

Output #1 do nothing
Output #2 reverse polarity

To most people shortcircuit is a bad thing. In most cases that is true. But instead of using the wire in one way (connects the + to a -) the wire is used as a 'loop' transporting the power from one piece of track to another. The shortcircuit creates a switch this way. I simply call it shortcircuit because if you would connect your 9V power to this connector it would short circuit when pressing the green button.


	All parts stuck together. The two connector points on the side of the control box, can be used to power the lights. I recommend a seperate transformer/speed regulator (see above). The 12V version fits immediately for the 9V another wire conversion is required. Note the plates used to support the connection Click the picture for a better view.

Putting it together
Now connect the pieces as shown in the picture. Make sure the light shows the colour equivalent to the button pressed, otherwise flip the connector.
Once done the train stops at the red signal and carries on at the green signal.
For reference, ideabook 7777 has a nice picture showing how the signal is connected on 12V track.
In fact, in the ideabook there are many examples of effective use of the signals (see pages 31, 49 and 52).