[sci.electronics] How to connect to TV composite video?

mort@apollo.COM (Stephen Moriarty) (11/29/88)

I remember hearing about a method by which one could connect
directly to the composite video of an ordinary TV. Does anyone
know how this is done? I believe I have found the correct point
on the schematic of my 12" B/W TV. I think there is an issue with
isolation, since the TV ground is the AC cold (black wire). Can I
simply use capacitors? How about linear optocoupling? The
application is to bypass the RF stuff of my home computer, i.e.
connect the computer composite video directly into the TV. Thanks
in advance.
-- 
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kez224@leah.Albany.Edu (K Zinssar) (12/01/88)

I built this modification into a TV about five years ago. I think there was
a project in SCIENCE & ELECTRIONIC magazine 5 or 6 years ago. It used
optocouplers and coiled wire around the xformer to draw off 12v to power
the board.
It sounds real simple, but there's more to it than there seems, sorry I
don't remember much, but this was done years ago in High School.
					Good Luck,
						Ken Zinssar
						Poor College Student
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