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Capacitor in my rc car? Answered

Hi. I just want to know what the point of this capacitor in my rc car is.


The brushes inside the motor generate tiny sparks - bursts causes by
the motor current being broken on and off. Those bursts are very
"sharp", if you look at them, the edges of the noise are like squares.
Sharp edges, for complex reasons, means that there is a lot of radio
energy in the waves of radio frequencies generated in the spark, which
interferes with other equipment - and the car too. Putting a capacitor
across the motor changes the shape of the edges, smoothing them over,
and making them emit less cruft.

Nice explain.

First I ever hard of the word cruft !!

And like its meaning, making cruft my word for the week.


4 years ago

It prevents commutator brush noise, limits arc-over brush erosion and prolongs motor life span. Pretty Neat ... don't you think ?

thanks guys. these are all great answers.

Supresses Electrical noise.

The electrical noise can interfere with the RC receiver giving false signals or changing the receiving frequency.

I think it helps filter electrical noise from the motor when power stops going to the motor and the motor is still spinning and generating it's own voltage.

it something to do with preventing "electronic noise" or something along those lines