Question about brushed motor diodes

[fredswain]

It's been a while since I've thought about this but from what I remember we used diodes (or were they caps?) across the positive and negative terminals of the motor with a lead soldered to the can. I believe this was done to minimize any glitching from noise to the receiver. I think. Please correct me if I'm wrong. If that is in fact what they were for, would they still be necessary with modern 2.4 systems?

[badattitude]

The caps were for the glitching and the diodes for motor/esc performance and braking IIRC. I use both the small caps and the diodes.

I still use both on the 2.4 system (2.4 is awesome)

You can try with the caps and see, it may be fine. The Diode will help you brake.

[jwscab]

caps are certainly a good idea, even if it's to prevent another guy on the track from glitching and crashing into you.

one cap from + to -, one cap from + to the can*, and one cap from - to the can* is the best (* or to the adjusting screw tab, on a modified motor). .15uF or thereabouts is typical.

diode is not needed unless you wanted to improve your braking, and definitely NOT if you use a reversing esc.

[Mad Racer]

Diodes or power caps were used to prevent power spikes going back to the esc when no power was on, ( braking or coasting ) especially when lower winds came out. ( More Rpm , more arching, more noise and Bigger power spikes) Caps were a MUST with X stall radios to to take any radio noise out. They really did work. I remember my first r/c venture a electric boat with a small outboard motor that my dad and i converted to r/c. It wouldn't steer as the interferance was so bad. My dad soldered 3 caps on and it was all good.

Later brushed motors had caps installed in the end bell. They were better as they didn't get knocked around.

When spectrum came out caps were history. Brushless came shortly after which don't need them as well.

Come to think of it in theory i would like to know why brushless doesn't need them. I guess no arcing which producers radio noise.

AAAAhhhhhh Later technology so much better, LOL.

[dldiaz]

Yes, theoretically you don't need capacitors with 2.4GHz radio system.

[jwscab]

brushless motors don't have the hard mechanical switching, it's all electronic commutation but can still be noisy.

[slow_jun]

No brush contact to a commutator, so no sparks and noise....