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Discussion Starter #1
My Pioneer Zephyr (MTH 20-20357-1) showed the MAINTENANCE REQUIRED warning the other day so I figured it had 50 hours on it. When I checked, I was surprised to see it had over 1000 scale miles and over 100 hours on it. I will add passengers while I have it apart for the gearbox lube. I’m also thinking about changing the lighting to LEDs using one or two of John’s LED regulators. There are places to hide the regulators in all of the cars, but since they are all connected with ten wire tethers and since the length that needs to be lighted (if I skip the baggage and RPO areas) is about the same as two Premier coaches, I may use just one regulator.

I’m a bit electronically challenged so when I get them apart and see what’s involved, I may just skip the LEDs. I was wondering if anyone else has changed the lighting on the MTH Pioneer Zephyr or the MTH Yankee Clipper to LEDs.

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Why complicate your life. Just use a regulator per car and wire them to track power, job done. I used one per car for my Aerotrain, those coaches are about 11 inches long. Just didn't seem forth the effort to try to save a few bucks and add wiring headaches.
 

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Discussion Starter #3
I may regret it later, but I’m sticking with the incandescent lights. There is not a good place to put the LED regulator in the observation car or the small coach. It won’t fit under the floor. The spot towards the front of the cars looks good from the outside, but there is plastic structure there to hold the contact springs. I could hide them in the rest rooms, but then I would need to alter the flooring and make something to hide them from view.

These cars are a royal pain to assemble. The body mount posts are inserted in almost ½” deep holes in the interior piece. It looks to me like when initially assembled, they put some of the posts in the holes, put glue on the shell and then assemble. I broke a few off during disassembly/assembly. I also found out (by decapitating the conductor) that adult standing figures are too tall for the main floor.

To preserve the incandescent lights, I’ll have to make sure I toggle the siding power off when this is parked on the layout.
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Discussion Starter #5
I generally stick the regulators to the ceiling on normal height passenger cars. But these cars are so low that adults can't stand up in the aisle. I was considering putting them on the roof above the rest rooms, but I didn't want to add screens to hide them. Maybe for the next lube in another 1000 miles or when the incandescent lights burn out, I'll give it another look. But for now, I'm happy. The train is finally making some revenue with paying passengers.

I used CA glue to stick the posts back on.
 

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There is not a good place to put the LED regulator in the observation car or the small coach.
I've cut the heat sink tab off the regulator to lower the height on a similar module.

The standard linear regulators are good for 1.5+ amp or 15 W with a heat sink. If a car has 10 LEDs at 10 ma each (100 ma total). Taking in 18 V and regulating that down for a 12 V LED strip yields a 6 V drop. That equates to 0.6 W. No need for the heat sink or the tab IMHO. I just cut it off with a pair of larger wire cutters then filed down the rough edge.

On another note, if the incandescent bulbs are screw in, there are lots of LED replacement bulbs made to screw into the socket. Then it's just a resistor and diode inline with the positive connection/wire to the bulb socket. You won't have constant lighting in conventional mode. If your have a constant track voltage (e.g., DCC) you'll have constant lighting. If it's DC track voltage you may need a bridge rectifier instead of a a diode to "cover all the bases".
 

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Discussion Starter #7
I have also cut the tabs from some of John’s regulators, but it still wouldn’t fit under the floor or the way I wanted it to fit inside the car interiors.

The stock lights are plug ins. I have plenty of spares from MTH cars that I have switched to LEDs. When they burn out, I could use my spares. I could also use these from Evan Designs.

Rectifier for LEDs
 

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I generally stick the regulators to the ceiling on normal height passenger cars. But these cars are so low that adults can't stand up in the aisle. I was considering putting them on the roof above the rest rooms, but I didn't want to add screens to hide them. Maybe for the next lube in another 1000 miles or when the incandescent lights burn out, I'll give it another look. But for now, I'm happy. The train is finally making some revenue with paying passengers.

I used CA glue to stick the posts back on.
FWIW, I've never found CA to work nearly as good as JB-Weld for stuff like the posts. CA doesn't have nearly as much shear strength as stuff like JB-Weld

I've cut the heat sink tab off the regulator to lower the height on a similar module.

The standard linear regulators are good for 1.5+ amp or 15 W with a heat sink. If a car has 10 LEDs at 10 ma each (100 ma total). Taking in 18 V and regulating that down for a 12 V LED strip yields a 6 V drop. That equates to 0.6 W. No need for the heat sink or the tab IMHO. I just cut it off with a pair of larger wire cutters then filed down the rough edge.
If you buy the right part, you can just fold the heatsink over and keep the extra surface while still reducing the height of the overall package. Of course, 100ma to the LED's in a passenger is way too bright, at least for me and most of the people I talk to. My regulator modules vary from around 3ma to 45ma constant current, and I've yet to have someone tell me the LED's aren't bright enough, even in larger cars.
 

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Yes to JB-Weld. If it's polystyrene plastic, Testor's model cement will be very effective as well.

The 100 ma for 10 LEDs was a worst case example to demonstrate the point. I've cut the regulator tabss, bent the regulators and considered replacing them with the 100 ma TO-92 package.

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I can tell you from first hand experience with a host of products that the TO-92 regulator package is not good for nearly 100ma unless the input/output voltage differential is only a couple of volts! The junction to ambient thermal resistance is 200 C/W! If you have an ambient of 35C, and you have just half a watt of power dissipation in the package, it's running at 135C! I've seen a number of Lionel smoke units where the TO-92 5V regulator got hot enough to melt the solder and drop out of the board! If I need more than around 30ma, I look for a more robust regulator.

FWIW, my initial design of my LED lighting module was with a TO-92 LM317. However, at the 45ma top setting the regulator would go into thermal shutdown after about 15 seconds, and that's at a 25C room ambient!
 

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Great info, John. You gotta' respect actual results.

I'm surprised a TO-92 package was used for a smoke unit; that the smoke unit needs way more power. But I'm in the pre-war world with some limited experience with postwar smoke units . Maybe the modern units draw way less power.
 
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