Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site lzwi.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxn!ihnp4!lzwi!nrh From: nrh@lzwi.UUCP (N.R.HASLOCK) Newsgroups: net.graphics Subject: Re: RGB to composite? Message-ID: <339@lzwi.UUCP> Date: Fri, 4-Oct-85 16:53:30 EDT Article-I.D.: lzwi.339 Posted: Fri Oct 4 16:53:30 1985 Date-Received: Sun, 6-Oct-85 04:41:31 EDT References: <10500004@uicsl> <338@gcc-bill.ARPA> Organization: AT&T Information Systems, Lincroft Lines: 28 Summary: atari technique In article <10500004@uicsl> hr@uicsl.UUCP writes: >A friend asked me if I would ask you: > Is there a simple way, say a chip, to convert RGB(I) signals > to composite video? >I doubt the application requires extreme precision. I think it may have >something to do with a Commodore 128. > harold ravlin > {ihnp4,pur-ee}!uiucdcs!uicsl!hr This is taken from my copy of the Atari 800 logic. comp video is sync + chroma + luminance luminance ---> op amp --------+----+-----> comp video --> rf modulator | | sync ---> op amp --> diode -->+ | | color---> op amp --> 100pf -> 1k --+ -- -- {ihnp4|vax135|allegra}!lznv!nrh Nigel The Mad Englishman or The Madly Maundering Mumbler in the Wildernesses Everything you have read here is a figment of your imagination. Noone else in the universe currently subscribes to these opinions. "Its the rope, you know. You can't get it, you know."