20,000 Hz, the frequency of many low transmitters starts at 56,000
Hz. The main reason for using the FM system is to offset the major
disadvantage of the AM system—namely, the interference of many
natural or man-made radio sounds, called “parasites.” Because the
weak signals of AM radio are quieter than the stronger ones, differ-
ences in signal level are formed, which are then perceived as noise.
AM receivers have no facility for cutting out these parasitic sounds.
To solve this problem, Edwin H. Armstrong invented a system
for eliminating noise caused by the power of the waves. Instead of
changing the transmission signal or the strength of the transmitter,
he changed the frequency of sound waves per second. Thanks to this
system, the amplitude of noise (strength of sound waves) could be
reduced to a minimum. But scientists are still mystified how
budgerigars manage to use this same system.
Of course, no little budgerigar can possibly work out for itself
from the time it is hatched how to apply a series of principles dis-
covered by man only after long trials. In the same way, no parrot can
know that it must produce auxiliary sounds in order to make con-
sonants distinct or to develop systems in its throat to enable it to do
so. Also, it’s not possible for such a system to be the end product of
a series of blind coincidences. All these complex systems we have
seen are without doubt, the work of God, the
Creator.
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