On 02/02/17 00:22, tony sayer wrote:
In article , Max
Demian scribeth thus
On 01/02/2017 17:01, Dave Plowman (News) wrote:
In article ,
RobertL wrote:
On Wednesday, January 18, 2017 at 12:50:08 AM UTC, Dave Plowman (News) wrote:
In article , NY
wrote:

It is generally accepted that human hearing is 20-20,000 Hz
(https://en.wikipedia.org/wiki/Hearing_range and many other sources)
and diminishes with age.

For those who go on about how good FM radio is they should note it
doesn't go anywhere near 20 kHz. ;-)

It goes to 16 kHz which is quite close.

They chose to cut it there so they coudl fit in eth 19 kHz pilot tone
and then use the bandwidth up to 38 kHz for th stereo difference signal.

Yup. They degraded the mono performance to squeeze in stereo. Nothing new
under the sun.

How do that degrade the mono performance then?..

You needed a steep rolloff at 16Khz and a deep notch at 19Khz applied to
the audio before adding in the pilot tone and subcarrier.
19Khz.

However what really screwed FM was going down to 100Khz channel spacing
with 200Khz in any local area.

You really needed wideband IF to get decent stereos at high frequencies,
and the sharp skirted IF filters needed to reject adjacent channels were
noticeably worse when applied :-(

Digital should and could be better.

--
"Socialist governments traditionally do make a financial mess. They
always run out of other people's money. It's quite a characteristic of them"

Margaret Thatcher