I have been asked to install a Tomar drumhead and rear marker lights on a Walthers Heavy Weight Observation car. I know the system works as diagramed. I am concerned about the slightly Mickey Mouse ballast bulb arrangement. Is there a way to accomplish the same results with using resistors or a bias resistor (I have heard this term, but don’t know what it means). I have no problem with space but heat might be a factor in a ballast bulb within the confines of the car. Dick Foster Arrow Creek and Western
Dick
Could you get away with an LED instead of a bulb? I have no clue how the drumheads are lighted but I would think a bulb would melt something. I had thought about useing a TCS lighting only decoder with a couple Bi color LEDs and a little fiber optic strands for markers on my cabin cars.
Pete
The Tomar drumhead light is a 1.5v bulb. If this car will be run on DCC you can use a resistor per any of the instructions for those bulbs on this or other sites. I went to the low end of the range after much testing to get the light to be visible thru the sign in a lit room. The resistor will work on DC, but the light will only be visible at near full track voltage. Are the markers lit by separate bulbs? Put the 3 bulbs in series and you now have a 4.5v bulb needing a much smaller resistor.
Not too long ago there were a coule articles in MR on constant lighting in cabeese using capacitors. these circuits will also work in the Obs.
Phil
Have you thought about using a LM317 voltage regulator set to 1.5v instead? I’ve used them (with a bridge rectifier) on DCC with no problems for passenger car lighting before. It also has the advantage of running quite a bit cooler. If the drumhead is the only thing to be lit, you could even use the LM317LZ (small transistor case).