[ale] Digital TV...

[rsj at radio.org]

--- On Fri, 10 May 1996 23:44:02 -0400 (EDT)  Unix Guru Dude <geof at denali.is.net> wrote:

>}Unix Guru Dude wrote:
>}> 
>}> }Geoffrey Myers wrote:
>}> }>
>
>FYI, the above are one and the same...  Probably get flamed for continuing
>this non-list topic, but....
>
># STUFF DELETED
>
>}> When you say 'interactive digital television,' do you mean a digital signal
>}> that is translated to an analog television?  Or do you mean you folks
>}> actually have digital televisions in customer homes?  The excerpt above
>}> refers to the latter, a whole new technology in televisions....
>}
>}We are running Digital Signal over an analog carrier to a cable box that
>}will translate on the fly.  Excrutiatingly good quality without having
>}to go and buy a new television. Plus ours is interactive with the system.
>}Order movies while you watch, WHEN you want to.  No waiting on Pay-per-view.
>}No returning the friggin tape by midnight the following day and no late charges.
>
>That doesn't make a lot of sense to me.  How do you send a digital signal
>over an analog line?  If it is truly then converted to analog on the fly,
>what have you gained?  I don't get it, sounds like a lot of sales talk to me.
>It's like saying you get cd quality from an analog tape when you copy a cd
>to tape...  I'd like to understand how this is done and why, if this works,
>other companies are going to the pains of creating a digital TV.

I believe that you are missing the point.  You need to separate the format 
of the data from the transport medium.  Only the CD is digital-digital all 
the rest are analog-digital.  There isn't any difference in using a DAT or 
other tape to hold the data (whether digitized/digital video or audio or 
data) and your hard/floppy disk.  They all just write 0/1's to the media 
instead of varying analog levels to the tape/disk. 

When digital information goes over cable/air(satellite) it is still digital 
information (0/1's)  The reason that you get a much better picture and audio 
when using digital is that poor signal strength does not cause loss of the actual 
data when it is digital as opposed to analog which gets noisy.  Most digital 
systems just look for the zero crossing of the signal at the proper clock time 
and decide whether it is a 0 or a 1.

The only digital-analog conversion that he indicated was at the converter in 
the home which would convert the signal to analog for the standard (by today's
standards) television set.  This is much the same as the current crop of DSS 
satellite systems do.

One thought just came to me, what is the difference between sending digital data
over the cablevision coax and over ethernet coax?

>
>} 
>}It's really sweet.
>}>
>}-----------------------------------------------------------------------
>}
>}Robert L. Harris
>}FSN System Administrator, Time Warner Cable.
>}e-mail: Robert.Harris at twcable.com 
>}        nomad at netwide.net
>}
>}###################################################
>}# Un*x FOREVER         # These are my thoughts    #
>}#                      #  and only my thoughts.   #
>}# Never Play LeapFrog  #  Any resembleance to     #
>}#  With a Unicorn!     #  anyone else's thoughts  #
>}#                      #  is either coincidence,  #
>}#                      #  or they stole them      #
>}#                      #  from me.                #
>}###################################################
>}
>}
>
>
>-- 
>Until later:
>Geoffrey Myers   geof at denali.is.net   Unix.Guru.Dude at worldnet.att.net
>	http://www.ticllc.net/~geof  or http://denali.is.net/~geof
>
>	Opinions expressed by me are mine, all mine, only mine.....
>

-----------------End of Original Message-----------------


Randy

---
Randy Jarrett  WA4MEI      | MAIL:
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