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Posted by G-squared on 01/01/06 05:18
John in Detroit wrote:
> Roy L. Fuchs wrote:
>
> >
> > The entire point was and still is that a preamplified antenna is
> > better than not having one. PARTICULARLY in the digital realm as
> > ghost signals, reflections, etc. are not a problem as they are in
> > analog reception.
>
>
> And my points were 1: Tain't necessarily so, (A pre-amplified antenna
> where I live for example would do more harm than good if feeding a
> single TV) and 2: It's easy to upgrade top end antennas
>
John, I'm with you on the preamps/antennas thing. Bad ones aren't worth
the bother
As for Roy and his blanket statements -- where do you start? Your
digital is converted to ANALOG to transmit it. I recommend reading
http://www.broadcast.net/~sbe1/8vsb/8vsb.htm
To make silly statements about the digital realm assumes you can
recover the analog to GET to the digital realm. ALL storage and
transmission devices ARE analog in nature. Internal to any device you
can have simple logic levels but to go to the outside world, even
within the same building, the digital becomes analog.Look at the 'eye'
patterns of a cd/dvd player or an SD data stream and you'll see what I
mean. To transmit it to your house and recover it is pretty amazing
given all the crap that can happen to the signal.
Think some about the 10.7 million tokens/second to stuff nearly 20
megabits into 6 MHz of bandwidth, the 1 of 8 power levels but those
levels are subject to reflections, attenuations and then add impulse
noises and it STILL works. WOW.
BTW ghosts (multipath) are a BIGGER problem in digital than analog. If
you get a 'minor' 93 nS delay/addition can trash an 8VSB stream (before
the equalizer) and only put a little bit of ringing into the analog
signal. Look at the research into the 'generation 5' decoder which is
basically a very elaborate receiver equalizer both in time and
frequency.
And THEN be RUDE about it. Oh well......
End of rant and BEFORE the new year -- so Happy New Year!
GG
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