Hello everybody: Does anybody know how to wire the four (4) wire #148 dwarf signal. I'm looking fore two(2) different ways too compelet this task? (1) would be via the insalated rail system. (2) the other which I really like is using a SPDT troggel switch. Please if you could make a drawing of your answer eith written explaintion. That way it really helps me out. Oh yes my transformer(s) are Post War ZW(s). Again Thank you in advance. Mike
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Looks like the 2 whites are common so treat them as 1 wire. The 2 reds go to the NC and NO contacts of the relay. You could use and insulated rail and relay. It is explained here
www.jcstudiosinc.com/BlogShowThread?id=410
Scan down you will see a block signal diagram.
Dale H
Dale. Thank you for answering. But I really don't understand what you said and your drawing. ASnd the NC and NO ?. Thank you so much Dale.
Your option (2):
The SPDT switch is replacing the 153C contactor in the Lionel instruction sheet. A typical SPDT switch (from Radio Shack, etc.) will be labeled "ON" on the 2 outer pins. The center pin may be labeled "C" or "COM" for common. The mechanical switch is simply connecting the "COM" pin to one or the other "ON" pins.
For option (1), an SPDT relay also has a "COM" pin but the other 2 pins are typically labeled "NO" (Normally Open) and "NC" for (Normally Closed). When the relay is energized, the "COM" pin is connected to the NO pin; otherwise it is connected to the NC pin. As Dale's diagrams show you must provide electrical power to energize the SPDT relay when a wheel straddles the isolated rail - this requires 2 additional components (bridge rectifier, capacitor).
I think your diagram blew a gasket Stan, you have a massive short circuit there! 
Do you mean on the upper left? That's the image copied from the instruction sheet. I think they're showing that 4 insulated wires come out of a hole in the case there rather than the 4 wires are electrically connected there...well, I hope that's what it means!
I thought those represented contacts Stan. In that case, it's probably fine.
Stan makes a good drawing and explanation. Just substitute the relay contacts for the switch contacts he uses. The additional relay coil circuit will take the place of manually throwing the switch. All a relay is,is an electromechanical switch. If the bulbs light up backwards,just reverse the 2 red wires.
Dale H
A Big Thank You: Dale & Stan thank you guys alot for the 1th class information that you have given me. Airborne!
Those openings in the drawings look like the represent the areas where the original 148 dwarf signal had screw terminals (3) for wiring.
The original piece, and the MPC 2115 signals used #19 pin based bulbs.
I am not familiar with newer dwarf signals, I guess they switched to a bulb with pigtails.
Pin based bulbs have been considered obsolete for some time.
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