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From: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Newsgroups: comp.sys.amiga,comp.sys.amiga.tech,comp.sys.amiga.hardware
Subject: Re: A3000 Video Chips
Message-ID: <272@cbmger.UUCP>
Date: 9 Jul 90 07:58:58 GMT
References: <4741@munnari.oz.au> <13060@cbmvax.commodore.com> <16713@windy.dsir.govt.nz> <13076@cbmvax.commodore.com>
Reply-To: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Organization: Commodore Bueromaschinen GmbH, West Germany
Lines: 17

In article <13076@cbmvax.commodore.com> grr@cbmvax (George Robbins) writes:
>
>The "subcarrier frequency" or more properly the system clock frequency is
>determined by the frequency of a crystal oscillator on the main board.  For
>NTSC it's 16*Fsc, while for PAL it's 16*(Fsc*4/5).  For one reason or another,
>these numbers are about 28 Mhz and within 1% of each other so it doesn't
>make a whole lot of difference....*except* if you are trying to generate
>composite video, where a 1% error in reference frequency is way out of the
>ballpark.

Heaven help! Does that mean that if we in Europe want to do video stuff,
we still have to build other mother boards with a different crystal?
1 % difference wouldn't be tolerable!

-- 
Best regards, Dr. Peter Kittel      //     E-Mail to 
Commodore Frankfurt, Germany      \X/      rutgers!cbmvax!cbmger!peterk