A<unk>  or<unk> form <unk>  is an electromagnetic<unk>  of constant amplitude and frequency; and in mathematical analysis, of infinite duration.<unk>  is also the name given to an early method of radio transmission, in which a carrier<unk>  is switched on and off. Information is carried in the varying duration of the on and off periods of the signal.  In radio transmission,<unk> <unk> s are also known as "undamped<unk> s", to distinguish this method from damped<unk>  transmission.
Continuous wave
Coiled coil
Electric current
Hot flash
Podalic version
Rhythm method
Lethal dose
The U Wave