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From: cayz@udel.edu (James Cayz)
Newsgroups: comp.sys.mac.hardware
Subject: Discharging CRT - Attach lead where?
Keywords: CRT Discharge
Message-ID: <28710@nigel.ee.udel.edu>
Date: 28 Aug 90 16:52:14 GMT
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All,

	Being somewhat technically oriented, I figured that the $30 investment
in the book "Macintosh Repair & Upgrade Secrets" might be worth it.  I do have
questions, though...

	In the Safety Techinques Chapter, Mr. Pina shows a picture of a CRT
Discharge Tool (1/8" screwdriver, wire, gater clip, & 10Mohm resistor), with
the tools attached to the Logic Board Rails (p. 11)...   Now, talking to a "Real
Apple Technician", they said "No, attach it to the strap surrounding the tube.".
Which (if not both) is more correct / safe?  Normally, I would try it either
way and see what happens, but since we could be talking blown parts (Mac and
human :-( ), I'd rather be a little more cautious and get at least 2 opinions
in agreement....

	Also, on page 131, "Analog Board - Removal and Installation", step 2 is
a little bothersome for me.  It reads:
"2. Physically disconnected the power cord from the wall outlet.  If you're the
least bit hesitant about discharging the CRT, leave the set disconnected
overnight.  By the next morning, most, if not all, of the high-voltage charge
will have dissipated."

	Huh?  Dissipated where?  I had even heard that since it is just a
static charge, a CRT charged would not lose it, but even when discharged, would
become (slightly) charged by sitting out unconnected in a low-humidity area,
requiring another discharge before re-connection.
	>>>>>	Which is Truth, and which is Urban Legend?   <<<<<

	Last Question:  I'm slightly paranoid about being blown around the room
by accidently discharging it across my hands.  Is there any _harm_ to
discharging it, lets say, whenever I work on / inspect / clean the dust out of
the Mac??

	Thanx for all the help in advance.
	James

|James Cayz can be found via:    USPS: Educational Technology Laboratory
|EMAIL Internet: cayz@louie.udel.edu : 203 Willard Hall Education Building
|PHONE: +1 302 451-6307              : University of Delaware, Newark DE 19716