Post by: jepinto on September 09, 2003, 02:35:36 PM
"jen-how do you get into these things? Are you NUTS? Didn't you ever learn to say NO?"
"Hey, he's a good friend, and you know, since the stroke..... And it's a learning experience, and it is our responsibility to "spread the word" and, and"
"But a video/analog board? What do you know about EMI and discharging a CRT, and making sure you're not a open circuit.."
"Well, there's two schools of thought here. One says the instructions "Discharge the CRT" is a liability issue, you know CYP (patootie), and the other says that you can even blow the CRT and cause an implosion rivaling the Big Bang in magnitude...."
So the question is
1. Does the CRT really require discharging?
2. Does discharging the CRT "blow" the CRT? Or is more along the lines of crossing the poles on a bad solenoid so you can start the car "one more time"?
-Bad spelling edit-
Post by: Epaminondas on September 09, 2003, 04:01:04 PM
If you are talking about fooling around the back of a naked CRT, you are dealing with high voltage that can kill you.
No one has any business fooling around with a naked CRT unless they know exactly what they are doing.
Other than that - I wouldn't worry about it.
There are home repairs and there are times to take a Mac in to the repair shop.
Best regards,
Epaminondas
Post by: Bill on September 09, 2003, 04:04:20 PM
She's talking to herself again!
Post by: bobw on September 09, 2003, 06:08:37 PM
Service manuals;
http://home.earthlink.net/~gamba2/manuals.html
Post by: Xairbusdriver on September 09, 2003, 09:05:13 PM
Shoptalk
LowEndMac
Apple's Troubleshoot and Repair Many other links here from the 'core!'
This one is REALLY scary!
Jim C.
I love the understated comments like: "Discharging the CRT before repairs will lessen the chance of electrical shock [and DEATH
] 
Post by: kelly on September 09, 2003, 10:06:20 PM
I haven't checked all the links.
But shops have tools to discharge it safely. You don't.
Trying to fix an old Tube TV 25 years or so ago.
I touched something I shouldn't.
It knocked me across the room and burned a little permanent scar on my finger.
I didn't do that again.
Post by: jepinto on September 09, 2003, 10:22:53 PM
Now wadda I do? It's in parts and pieces, new part sitting there calling to me......
Post by: kelly on September 09, 2003, 10:26:35 PM
Call a shop and ask them what you should do.
All they should charge is the labor. No?
Post by: jepinto on September 09, 2003, 10:45:06 PM
Problem is finding a shop.... there's one chance in less than 60 miles. And only if he is willing to take it on.... I'll find out Wednesday.
Post by: Epaminondas on September 09, 2003, 11:30:08 PM
Don't touch it. Don't let anyone else touch it.
The biggest danger here is to the visiting friend, neighbor, or grandchild. A note to "Do Not Touch" will likely have the opposite effect on any intrested, inquiring mind.
The capacitors associated with a CRT store considerable current, even when the CRT is unplugged for considerable periods. I have heard one story (Internet) similar to Kelly's involving an old CRT that had been stored in the attic for several years. The assumption was that the charge had dissipated in the interim. Wrong assumption. Knocked the guy on his rear - thankful to be alive. The guy seemed credible - tough ol' no-nonsense fixit type. True or no? I choose not to seek the answer question scientifically.
But I do know for a fact that it really is hard to perform CPR on yourself. Particularly when you are unconscious at the time.
You got yourself into this one, Jennie. I'm sure you will find your way out.
Do take care,
Epaminondas
Post by: sandbox on September 10, 2003, 12:25:58 AM
http://www.repairfaq.org/REPAIR/F_captest....tml#CAPTEST_008
Post by: Dreambird on September 10, 2003, 01:55:40 AM
BTW...
jen-how do you get into these things? Are you NUTS? Didn't you ever learn to say NO?
Post by: gunug on September 10, 2003, 07:56:41 AM
Post by: Xairbusdriver on September 10, 2003, 04:18:11 PM
QUOTE
Apple tech references that showed using a screwdriver with a wire wrapped around the top of the blade with the other end hooked to the chassis ground of the CRT.
But that's not the complete description of the tool. Read the links, one of them is from Apple and describes how to construct this type of tool. It recommends a 10megohm resistor. That's not a very conventional, in-most-scrap-box resistor! If you simply use a screw driver (or some other metal object) you will likely damage some thing on the mother board and quite likely your self!
Probably will melt whatever that object was, also...This is not rocket science, but you must know what you are doing to do it safely. It is one of those things Mr. Wizard used to say, "Kids! Don't try this at home!" Which, of course, created lots of terror in many homes!
Jim C.
Post by: gmann on September 10, 2003, 06:17:41 PM
Post by: jepinto on September 11, 2003, 06:58:59 AM
3.141 hours? couple of days? a week?
Post by: kelly on September 11, 2003, 09:02:47 AM
So they're talking you into it?
I'm sure it's easy for someone who knows just what they're doing.
Do you have the tool and know just what to do now?
I still don't recommend it Jennie.
Post by: jepinto on September 11, 2003, 10:35:26 AM
QUOTE(kelly @ Sep 11 2003, 10:02 AM)
So they're talking you into it?
Yep, the voices are real loud this morning.
Post by: Bill on September 11, 2003, 04:39:32 PM
If I recall (correctly is another matter), way back when ... was is not you who was asking 'how' to strip insulation off small gage wire.?.
If this was the case. Listen to what Epaminondas, Kelly, Airbus driver is telling you girl.!.
Post by: jepinto on September 11, 2003, 08:26:40 PM
My mama din't raise no dummy. I'm not gonna do the discharge. I've found someone with more experience (which in this case is any at all) to do the discharge. Then I can do the replacement.
Post by: gmann on September 11, 2003, 09:09:49 PM
Post by: Bill on September 11, 2003, 09:26:44 PM
Post by: jepinto on September 11, 2003, 10:16:05 PM
Post by: Xairbusdriver on September 12, 2003, 09:38:17 PM
It also requires that you maintain a certain degree of decorum in your dress style (or should that be 'pant' style?
)! 
And I'm not even going to mention your 'stripping' comments! 
BTW, newer Apple CRT's (which are getting hard to find now that the eMac is the only one using them!) included 'bleeding' resistors in the circuits to drain this high-voltage after they were turned off for a while. Of course, it was discovered, by some less than careful tech, that the resistors could sometimes fail!
Jim C.
Post by: sandbox on September 12, 2003, 11:59:27 PM
http://www.lowendmac.com/tech/crt.shtml
http://users.creative.net.au/~mla/mla_site/crt.html
“I would especially like to hear from people that have actually
died from a CRT discharge.”
LEMBill
http://www.mail-archive.com/compact.macs@m...m/msg08186.html
striptease