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From: msc@saber.UUCP (Mark Callow)
Newsgroups: net.video
Subject: Re: MTS and Cable T.V. questions, comments
Message-ID: <1913@saber.UUCP>
Date: Tue, 21-Jan-86 19:41:35 EST
Article-I.D.: saber.1913
Posted: Tue Jan 21 19:41:35 1986
Date-Received: Thu, 23-Jan-86 21:21:09 EST
References: <19@valid.UUCP> <179@oberon.UUCP>
Distribution: net
Organization: Saber Technology, San Jose, CA
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> When channels 2-13 and 14-83 were originally assigned frequencies they were
> given, by todays standards pleanty of guardband.  When television started 
..
> came cable television.  They were looking to put even more channels out there
> than there already were so that there would be no conflict with exhisting 
> ones.  The went up the frequency scale but after a while you are not
> talking electro magnetic any more, eventually you get into micro waves and
> the Light!  They went to pack the new channels together (those above 83).
This is incorrect.  Channels 14-83 are UHF broadcast channels.  No cable
system that I have seen can deal with UHF signals.  They all deal with
VHF.  The extra channels are not obtained by squeezing the existing channels.
They are obtained by using frequencies that in broadcast use are assigned
for uses other than TV.  For instance the so-called "mid-band" cable channels
occupy space between TV channels 6 and 7.  In broadcast use you will find
several FM stations in that frequency band.
> 
> However this does not limit the way that you receive broadcast channels, 
> they are just passed on to you in the original form (easily discovered
> by connecting the TV w/o the cable box).  Thus any channels 2-83 that
Only channels 2-13 can be passed through "directly".  And as someone else
pointed out some cable systems' head ends demodulate even those to IF and
remodulate.  On our cable system the head-end equipment passes the MTS
signal so broadcast channels 4 and 20 (4A and 3B on the dual cable system)
MTS signals come through just fine (if you hook the cable directly to the
TV) The problem is with the Zenith ZTAC descrambler/converter.  It loses the
MTS signal.
-- 
From the TARDIS of Mark Callow
msc@saber.uucp,  sun!saber!msc@decwrl.dec.com ...{ihnp4,sun}!saber!msc
"Boards are long and hard and made of wood"