Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site masscomp.UUCP
Path: utzoo!watmath!clyde!bonnie!masscomp!rtc
From: rtc@masscomp.UUCP (Richard Carling)
Newsgroups: net.video
Subject: Re: Cotten Club Anti-Piracy
Message-ID: <677@masscomp.UUCP>
Date: Mon, 29-Apr-85 12:14:26 EDT
Article-I.D.: masscomp.677
Posted: Mon Apr 29 12:14:26 1985
Date-Received: Tue, 30-Apr-85 07:14:01 EDT
Distribution: net
Organization: Masscomp - Westford, MA
Lines: 20

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I don't know if this is the technigue the Cotten Club is using
to stop TV taping but I know one method proposed for making cable
and broadcast video unrecordable on VCR's is as follows.

The vertical sync is run faster and slower during the broadcast instead of
remaining constant. A TV has no problem adjusting to the shift
but a VCR which has mechanical timings to deal with (head spinning
and tape speed) can't lock to a signal that varies significantly from the
expected frequency.


  To record such a signal (yes, there is always a way) requires the
use of a Time Base Corrector (TBC). These things currently cost around
$2K (at least) but if such a technique was used, the market for TBC's would
drastically increase and the cost would come down.


                                        Richard Carling