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Old March 18th 14, 12:47 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.misc
Jerry Stuckle Jerry Stuckle is offline
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First recorded activity by RadioBanter: Oct 2012
Posts: 1,067
Default Quad shield coax & dielectric?

On 3/18/2014 5:11 AM, Rob wrote:
Jerry Stuckle wrote:
That was the major impetus over here to switch to digital - to free
up major bandspace in the VHF and UHF spectrums.

The 'freeing-up' is because each QAM multiplexed transport stream
carries typically up to 6 TV channels and 6 high-quality stereo radio
channels.


Ah, so the channel is effectively only 1Mhz wide then.


That is only an "average" that you get when you divide the total bandwidth
by the number of TV programmes transmitted.
As multiple TV programmes are transmitted on a single channel,
that occupies the width of a classical analog channel that could
transmit only a single programme, more programmes can be put in
the same bandwidth.

However, to receive one of them you really need to receive the
entire channel (several MHz wide), so all link budget calculations
should be based on the full bandwidth. Later, the receiver throws
away most of the bits it has received and decodes only the information
for one of the TV programmes.


You need to check on how the signals are transmitted. You seem claim to
know a lot about how U.S. TV works, even though you're thousands of
miles away. But then you know a lot more about my job, the people I
work with, and the tools I use than I do.

Come on over and do my job for about ten years. Then maybe, just maybe,
you'll be qualified to comment on it.

Otherwise, I just consider you a troll.


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