I'm assuming your discussing capacitors which are attached across the positive and negative leads on the Electronic Speed Control (ESC) used in battery powered vehicles.
- Those caps are installed to capture "electonic noise" or "push back" , or "back EMF" (aka sparks) created by the motor operation, before it gets into the rest of the electical system (ESC,servo etc). In this mode they help prevent stray electricity/signals from entering the system and thus cut down on what you are calling "jamming". Think of them as small surge protectors.
- Secondarily, the caps can help the ESC run a little cooler by dissapating those "sparks" before they get into the ESC and generate heat.
- The energy captured by the cap is stored in the cap until the ESC gets its next "full power" command. Then that small amount of captured power flows to the motor along with the electrical power drawn from the battery.
-With or without ESC caps, it is still always a good idea to install your receiver and its antennae as far as practically possible from the ESC.
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