Missing J78 and J79?
A few people have emailed me regarding the fact that they do not seem to have a J78 and J79 jumper on their analog board! After reading the CC forum, I found a solution (special thanks to James Corless for the information).
Note: This section is ONLY for those with an actual Macintosh Color Classic II (Performa 275) analog board OR for those without a J78 and J79 jumper on their analog board.
If you are missing J78 and J79, your analog board should look like this:
Using your dremel, cut the connection to the 20-pin.
Use a meter to verify the disconnection. And that's it!
[NOTE: it appears some people have had lots of problems with this particular point of the modification. The above instructions appear to be at least incomplete, possibly entirely incorrect. Mr Watanabe of the CCSCC has an excellent explanation of sense line coding on one of his pages, and there is an explanation of the resistor addition that needs to be done in order to satisfy the High-Res sense coding at the web page (English Babelfish translation) of a certain "Mr. Hirotac". PLEASE read these video modification pages thoroughly and understand the sense line coding issue before attempting the mod on an analogue board with no J78 or J79. -Chris Lawson]
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