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Am in receipt of my first MTH Madison cars, a trio of CGW beauties, and my only complaint is that the LED lighting is far too bright.  Since I'm in the process of 3RSing them, I took the first of them apart (RPO) and can find no dimming adjustment as is found on GunnerJohn's excellent lighting units.

I hate to have to replace the entire system for want of a dimmer.  Is there a way to dim the units, as is, or can a resistor be added somewhere in the circuit to tone them down?  I have no need to vary the brightness, once dimmed, so a rheostat or potentiometer is not necessary - if there's an alternative.

My level of electronic expertise is demonstrated by the fact that I had to look up the spelling of both "rheostat" and "potentiometer".  Ignorance is not bliss.  Please HELP!

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You can add a resistor to tone down the light intensity.  Without seeing the exact wiring, I can't be totally specific.  I believe it's going to end up being as simple as the resistor in the main wiring to the lighting board. The value of the resistor will likely have to be determined experimentally to achieve the desired brightness, I'm think along the lines of from around 100 ohms to maybe 250 ohms, and probably 1/2 watt will be plenty as far as size.

I have a bunch of the MTH Woodside Strasberg passenger cars, and one thing I noticed right away was no flicker resistance!  I added a cap to one to cure that, and when I get the time, I'm going to do the rest.

Sadly, tests of several resistors, of varying values, didn't put much of a dent in the LEDs' brightness.  Frustrated, I removed the little resistors that fed two of the five LEDs and that didn't get close to my goal, either.  Then, it occurred to me that a defuser might help and disguise the LEDs in the by going.  Unable to find anything likely in the parts heap, I finally hit upon another, much simpler idea: spray paint the LED side of the entire lighting circuit board white!

I masked off only the large "can" capacitor and the little resistors at the track voltage feed end, gave it a good solid single coat of Krylon Fusion white and it worked!  The LEDs now generate a golden glow worthy of the now-defunct headlight company's name and I'm ready to take on the rest of the fleet.

20181012_131532

The only remaining question was, "Is this safe?"  LEDs don't generate any heat to speak of and the Krylon fusion paint does not appear to be conductive.  Regardless, the volts and amps involved are so low that fire seemed a remote possibility.  Consultation with one of our great OGRF Electronics Luminaries confirmed that there should be no safety issues. However...

DISCLAIMER: Use this simple, effective solution at your own risk.

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