AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-low carrier frequency
On Mon, 2 Jul 2007 17:08:43 -0600, "Bob Myers"
wrote:
" wrote in message
...
Better still, Vestigial Sideband!
You're both wrong. It is VIRTUAL SIDEBAND
Nope - VSB, as commonly used in broadcast television,
most definitely stands for "vestigial sideband" - a form of
AM in which the carrier and part of one sideband (in this
case, the lower sideband is the "vestigial" one) are retained,
along with one full sideband which carries the information
(in this case, the upper sideband, which carries the luminance
(Y) video information).
Bob M.
It is definitely vestigial side band. There is a bandpass filter in
transmitter to get rid of much of it when the signal is generated, and
generally a tuned coaxial stub on the antenna to get rid most of the
rest of it.
Effectively NTSC television is single sideband with carrrier (while
SSB is technicall SSBSC, Single Side Band, Supressed Carrier, which is
considerably more difficult to generate and detect).
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