[William Sommerwerck]

"Dave Plowman (News)" wrote in message ...
In article ,
Frank Stearns wrote:

Take one of the Big Audio Debates of the middle 20th Century -- should
radio transmission move from a 5 Khz bandwidth to a 15 Khz bandwidth?

I don't quite understand this. In the UK, AM radio transmissions (until
long after FM arrived) were not all restricted to 5 kHz. That came later
by international agreement as the AM bands got overcrowded. The individual
radio receiver, however, very likely did restrict the bandwidth to 5kHz or
less. But those wishing high quality radio reception used FM anyway - not
only for the wider frequency response, but better signal to noise ratio,
and being less prone to interference.

This is a complex story. Suffice it to say that AM in the US was always
"narrowband", simply to make room for the stations needed in such a large
country. There were exceptions. WQXR -- a classical AM station -- had 10kHz
bandwidth for many years (it probably still does), and was located at a
frequency where its sidebands wouldn't cause much interference with distant
stations.

FM is inherently wideband and quiet. Not surprisingly, the head of RCA, David
Sarnoff (a man of debased rottenness arguably greater than that of the Waltons
and the Kochs combined), wanted to block or even destroy FM. He assumed that
low-noise, high-fidelity sound would destroy the AM infrastructure he had
worked to build -- and that was not permissible. * Part of his efforts
included driving Edwin Armstrong -- the man who developed wideband FM -- to
suicide.

You can read about this in a number of books, and draw your own conclusions.

* He apparently overlooked the fact that FM radios were -- and for many years
would remain -- expensive, putting them beyond the average listener's reach.