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Right then… after the saga of protecting my SCX lights with a 100 ohm resistor, which allowed a running time of 10 minutes before they suffered a total existence failure, I've taken them out and replaced them with some home brew ones.

2 LEDs in parallel and a resistor in series.

They work but they flicker, irrespective of the amount of throttle being applied. Any ideas?

The SCX supplied rear lights take their power from the same rails in the car and work fine.

Regards,

Confused of Manchester
 

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Led's in parallel with a common series resistor is not a good idea, as one led with a slighly lower forward volt drop can "steal" all the current. Not sure about flickering, but try the Led's in series. You may need to adjust the series resistor for the required brightness.

Rich
 

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Led's in parallel with a common series resistor is not a good idea, as one led with a slighly lower forward volt drop can "steal" all the current.

Would this cause one to light and not the other?

Both my LEDs are lit simultaneously… but flash simultaneously.
 

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Are you sure that these are not flashing Led's
Try them on a PP3?

Rich
 

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Rich Dumas
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Possibly the car is not getting good power because the braids need to be cleaned or adjusted. You might have a poor connection in the wiring for the lights. If you run the car around the track at a constant speed what do the lights do? SCX does use a voltage regulator which minimizes, but does not eliminate flickering. In order to eliminate flickering you also need to have a storage capacitor. I am guessing that your home brew lights only include the LEDs and dropping resistor. With no regulation the lights would flicker a lot more than the original SCX system.
 

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Work in stages, to eliinate problems. If this is analog the brightness will vary with throttle position.

Put the led's in series, add a series diode and series resistor. Try it on a PP3. If ok try it straight across the track, if still ok connect to the slot guide.

Rich
 

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I've been trying a slightly different solution to the dead SCX leds. I've put the following in series LED-Resistor-LED. I'll let you know if it proves reliable.

Are you sure the flickering isn't due to a dodgy connection somewhere?
 
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