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From: dave@boingo.med.jhu.edu (David Heath)
Newsgroups: sci.electronics
Subject: Re: Adding video/audio jack to a TV?
Message-ID: <1991Apr28.200830.28926@boingo.med.jhu.edu>
Date: 28 Apr 91 20:08:30 GMT
References: <1991Apr24.185624.17475@amd.com> <1991Apr26.151518.24003@tc.fluke.COM>
Distribution: usa
Organization: The Johns Hopkins Hospital-Body CT Imaging Lab
Lines: 23

strong@tc.fluke.COM (Norm Strong) writes:
>In article <1991Apr24.185624.17475@amd.com> mmpjh@brahms.amd.com (Javed Hussain) writes:
>}Hello netters!
>}I was wondering if I disconnect the line called VIDEO and connect it to
>}video out of my VCR, will it work?

>I wouldn't recommend this.  Many TV sets have off line power supplies that
>leave the chassis hot.  They get away with this because the antenna is
>transformer coupled, and all the controls have plastic shafts.  

>If you insist, then check the potential of the chassis relative to ground
>with the plug inserted in both directions.  If it's completely cold,
>you're safe.  

I have made similar modifications to a televisions in the past. In both
cases, there was room inside the set to install an isolation transformer
on the AC line. You have to be careful that the magnetic field from the
transformer is not strong enough to distort the picture (especially on
color tv's.) 


-dave heath
dave@boingo.med.jhu.edu