Flicker Free lights using a Super
Capacitor and Fibre Optics.
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See suppliers of
fibre optic cable.
Lights in passenger
coaches and vans have the annoying tendency due to their light weight and poor
track pickups, to flicker while operating in a moving train. Using a similar
circuit as the one below will reduce this flicker effect, keeping the LED Tail
Lights on steady, in the vans.
The circuit below is
from a
This
circuit can be used on both DC and DCC to power all the LEDs and will
allow any form of cheap easy pickup to be used (see photo). This circuit could
be tried on a passenger coach with incandescent lamps but due to their higher
current requirements may require more capacitors or use the 1 farad Super
Capacitor that is now available.
Also if you have
passenger coaches with lamps that are causing problems with the DCC Booster
Circuit Breaker resets (see below), this circuit could be modified to supply
the lamps.
This circuit if used
on DC is not polarity dependant. If requiring directional tail lights on a
guards van, some form of switching selecting one of two LEDs that will have the
fibre optic cables attached to. This will be left to each individual to
determine how to do this.
Incandescent lamps draw 15 to 40 mAs and LEDs
typically draw 20 mAs.
Using High Intensity LEDs (LEDs in 2010 have a much
higher Intensity rating (brighter) than earlier LEDs), adjusting the Voltage
Dropping resistor you can have currents that provide a good intensity to less
than 1 mA, experiment here. The lower the current being consumed from the Stay
Alive .047 Farad Capacitor, the less flicker effect and the longer the LEDs
remain illuminated with power removed (lost during running).
Passenger coach lighting can be better using
incandescent lamps due their better overall 360 degrees radiating pattern where
as LEDs have a very directional beam.
Painting the interior of a Passenger Coach with Semi
Gloss paints, will radiate the light and will allow the use of lower power
LEDs. For an example, click on DCC Concepts
Flicker Free Kits and an Installation
Scroll down the page.

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The components soldered
together and attached to the wagon floor or suitable location with Blu Tak. Blue cylinder is
the Super Capacitor. Note: The black
stripe on the zener diode is connected to the positive supply. |
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Drill holes the
same diameter of the fibre optic cable in the body where lights are to be
located. 0.7 mm in this case. With the fibre
optic cables located, apply the barrel of the soldering iron to mushroom over
the end so that the cable does not disappear into the wagon. |
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Drill 2 holes in
the LED to locate the fibre optic cable. This must be a tight fit. Do not super glue
the cables in the LED. Be careful not to
drill too far into the LED body and damage the LED element. The resistor used
for the LED is not critical. 1,000 ohms will be sufficient, but if using a
few LEDs for coach illumination, you may need to increase resistance to
decrease the current. |
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Make some easy
simple pick ups for the wagon. These do not need to be great as the circuit
will compensate for poor power pick up. As shown, I used
0.4 mm phosphor bronze wire and just drilled a 0.4 mm hole through the bogie
bolster. Solder wire to
pick up and through hole to the bridge rectifier. Remember to have
the axles reversed on the other bogie. |
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This is the final
product on the track and running around the layout, no evidence of
flickering. See how you go. |
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