Electronic speed control. An electronic speed control or ESC is an electronic circuit with the purpose to vary an electric motor's speed, its direction and possibly also to act as a dynamic brake.
The ionosphere is the layer of the atmosphere that reflects radio waves. This effect is caused by the ionization, or electrical charging, of the gas particles present in the upper atmosphere by... The ionosphere is the layer of the atmosphere that reflects radio waves. This effect is caused by the ionization, or electrical charging, of the gas particles present in the upper atmosphere by X-rays and ultraviolet rays emitted by the sun.
It is much the same with radio waves. AM waves bounce off the very large structures involving charged particles in the ionosphere. The shorter wavelength FM waves are better able to see the 'holes' between the ions, and do not really reflect off the ionosphere except for a faint 'ghosting'.