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From: brown@vidiot.UUCP (Vidiot)
Newsgroups: sci.electronics,rec.video
Subject: Re: TV Descrambler
Message-ID: <808@vidiot.UUCP>
Date: 24 Sep 90 17:39:50 GMT
References: <477@wybbs.mi.org>
Reply-To: brown@vidiot.UUCP (Vidiot)
Organization: Vidiot's Hangout
Lines: 22

In article <477@wybbs.mi.org> hcliff@wybbs.mi.org (Cliff Helsel) writes:
<I found the following instructions in a text file on a bulletin board and
<wonder whether this will do what is claimed.

This only works on systems that use carrier interference, ie, a signal that
is equal to carrier heighth is added about 2.5 MHz above the carrier.

What this does is cause the AGC of the TV's tuner to believe that the signal
is real strong, so it buries the signal in the mud by reducing the signal gain.
What this circuit does is become a notch filter for this extra carrier.
The version given is very broad and needs to be changed to a fixed capacitor
within the notch needed for the particular channel and a very small variable
cap to fine tune it.  Also needed is a variable pot for the `Q' adjustment.
The whole idea is very touchy and needs to be re-adjusted every couple of
weeks.

This method will not work for active methods of scrambling.  This is a passive
method only.
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