Among the main names related with
the improvement of the modern radio receivers are:
Earnest Humphrey Scott,
pioneer in the production of state of art receivers;
Edwin Howard Armstrong,
inventor of the three main types of circuits: regenerative,
superheterodyne and frequency modulation.
Louis
Alan Hazeltine Louis Alan Hazeltine. Professor of Stevens Institute of
Technology, USA, developed the neutrodyne circuit. Hazeltine
theory led largely to lifiting the thermionic valve amplifier
out of the realm of experimentation and into the realm of calculable
engineering.
In the neutrodyne circuit both tuned radio frequency and audio
amplification has a kind of stabilizers, known as “neutrodons”
by mean of which the circuit is balanced out, or neutralize
the nowls caused by the valve's oscillation.
In the chaotic time in the twenties when broadcast listners
were beset by howls the neutrodyne circuit was a great success
and Hazeltine has been considered as an inventor whose main
tools were the pen and the slide rule, tooking the squeks and
howls out of the radio receiver.
The term "neutrodyne" was coined by Willis H.Taylor,
Jr. a participante of the Pennie-Davis-Marvin-Edmond associated
attorneys an office specialized in patents. Originally the term
was used by the independente group of radio manufacturers to
find a solution for patent litigation based in the Hazeltine's
work.In the beginning the independent group of radio manufacturers
basically comprises: F.A.D. Andrea, (FADA), Freed-Eisemann and
Garod.The term "Neutrodyne" was used as a trademark
as soon as the first radio receivers were launched in the market
by FADA in 1923.
