On Tue, 27 Dec 2005 23:09:07 -0600
Jim Leonard <trixter at oldskool.org> wrote:
Scott Stevens wrote:
It's VERY important to be careful inside the
Mac once the cover is
off. It's extremely easy to snap the glass nipple on the CRT and
ruin it. Apple in their infinite wisdom put a circuit board on
the back of the neck to act as a 'torque amplifier' for this
purpose. Just bumping the board wrong can let all the 'magic
vacuum' out of your CRT.
Geez -- so is that the board I see at the top of the tube in this picture:
http://modeltrain.com/mac/se30/6.jpg
I bump that board and the tube will implode?
There is a better chance of that happening than is acceptable.
There is a long thin glass nipple that pokes through the socket
connector in the center of that board. A minor bend of the board
is enough to snap off said glass nipple. I have opened my
compact Macs often enough without it happening, but that's
because I am very aware of the problem, having broken the first
Mac Plus I opened years ago. I was able to swap out the CRT on
that one, it was in the era when spare CRTs were pretty common
for $10. They're NOT as common any longer. Best practice is to
unplug the board immediately after opening the case (and then
stay clear of the glass nipple, which protrudes out).
It is NOT one of Apple's best designs. But they were
deliberately keeping the layman out of that generation of Mac.
(Steve Jobs was rather snide about the 'hacker proof' nature of
the original Mac in a radio address I heard him give back at the
launch of the Mac- it put me off Apple hardware for a long time)
Apparently the priesthood 'allowed inside the case' were properly
warned.