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Errors in some editions of the 30th-anniversary Red Book

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I recently decided to capture the rev. 0 Apple II schematic from the
"red book" reference manual into KiCad and sync it up with the PCB layout
done by Mike Willegal a while back so that there's a complete ECAD resource
for the Apple II.

I originally had a copy similar to this:

https://ia800202.us.archive.org/9/items/Apple_II_Redbook/Apple_II_Redbook_text.pdf

It looks like a 1-bpp scan at somewhere around 200-300 dpi.  It's not the
prettiest, but it'll get the job done.

A while back, I had replaced the PDF I had with the version available here:

https://www.apple2history.org/2023/05/01/red-book-revisited/

This one looks like everything was cleaned up, including the schematics. 
Unfortunately, some errors were introduced:

1) Junctions are usually marked in a schematic with a dot.  In this edition,
the junctions have gone missing, which makes it more difficult to suss out
what's supposed to be connected.  As an example, go to page 143 and look at
the crystal-oscillator circuit.  There's a junction where the collector of
Q1, the side of R2 that isn't grounded, and one side of XT0001 come
together.  There's another between the other side of XT0001, the base of Q2,
and one side of R4.  These (and others) are missing from the 2023 edition.

2) Bipolar junction transistors (BJTs) have an arrow drawn on the emitter
that either points toward the base (for a PNP transistor, like the 2N4258s
used in the crystal-oscillator circuit) or away from it (for an NPN
transistor).  The 2023 edition is missing these arrows, which makes it
difficult to determine which is the emitter and which is the collector.

You could figure these errors out if you have the PCB layout as a guide, by
cross-referencing with other available schematics, or if you have knowledge
of how the circuits are supposed to work.

The initial release of the 30th-anniversary edition has fewer cleaned-up
pages:

https://apple2history.org/dl/redbook.pdf

The schematics in this file appear the same as in the original.

-- 
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(IIGS( https://alfter.us/         Top-posting!
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Errors in some editions of the 30th-anniversary Red Book scott@alfter.diespammersdie.us (Scott Alfter) - 2025-07-18 15:39 +0000
  Re: Errors in some editions of the 30th-anniversary Red Book D Finnigan <dog_cow@macgui.com> - 2025-08-07 12:37 +0000
    Re: Errors in some editions of the 30th-anniversary Red Book scott@alfter.diespammersdie.us (Scott Alfter) - 2025-08-07 16:32 +0000

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