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Re: Apple][VGA - finally available
To: Immortal Nephi
Re: Re: Apple][VGA - finally available
By: Immortal Nephi to comp.sys.apple2 on Thu Jul 03 2008 12:47 pm
I'll answer both questions in a single message:
Yes, the a2vga needs an adapter to grab signals from the AUX slot. But there is
not going to be a clearance problem, because the 80-col card still sits in the
connector where it used to be. The adapter surrounds the card and sits on the
other side of the slot's contacts. I can't make you a photo, because I just
sent the only adapter I have to Henry Courbis, who will present the card on
KansasFest.
You can't compare the Mega II chip and the Apple][VGA, because the decoding
done on the Apple][VGA is just a copy of an NTSC TV's color decoder. It is
analog circuitry! The decoder is somewhat reduced, because, for example, there
is no need to recover COLOR REFERENCE from the signal because it is already
present. A similar circuit is used in the PAL color card and the PAL Apple //e
to partially decode the NTSC signal so that it can be encoded to PAL again.
About the schematics: I published them in the "manual" on the web page.
Ferdinand Meyer-Hermann