433MHZ=433 waves in a 1 us or 216.5 waves in 0.5 us. if i measure the time period of those 216 waves then frequency can easily be calculated. In FSK we need at least 2 frequencies for 0 and 1 .lets say 433,000,005 hz=1 & 433,000,006 for 0. This never happens in real world why?