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Christine1234

macrumors regular
Original poster
Mar 2, 2011
161
10
Snowflake, AZ
My eMac G4 is having intermittent blurry screen problems. It's not just in Safari, it happens with my documents and everything else that's typed too, and I've tried adjusting the resolution with no luck. The dock and my desktop aren't affected. I've tried posting about this twice in the Mac Basics and help section, but the first time, several months ago, no one responded and this time I was directed to come here. It's becoming more frequent. Any ideas or thoughts on how I might cure this?
 

adcx64

macrumors 65816
Nov 17, 2008
1,270
124
Philadelphia
The eMacs were plagued by bad capacitors. This might be the problem in this case, or the flyback transformer on the CRT.
 

Goftrey

macrumors 68000
May 20, 2011
1,853
75
Wales, UK
If it is the flyback transformer, are you getting a high pitched squeal coming from the eMac as well? If not, as adcx64 said, it'll most definitely be the capacitors :(
 

Christine1234

macrumors regular
Original poster
Mar 2, 2011
161
10
Snowflake, AZ
Watch out when working with the CRT. They contain dangerous voltages that can kill you...

I have another computer (iMac g3) that can be used for a few weeks. From what I've read, if you wait a few weeks, the voltages go down to a point where they're no longer dangerous. That sounds like a good plan, even though I don't plan to mess with the CRT.
 

bigeasy_uk

macrumors 6502
Sep 8, 2005
273
12
Leamington Spa, England
Apparently newer emacs have a bleeder resistor built into the flyback, but they can fail, so please be careful. When I'm working in my arcade machines, or even just changing a game board I'm always weary of the monitor as they are always exposed and even if I don't electrocute myself I don't want to break the neck, 28" monitors are getting rarer and cost a fortune to ship!

Here's a good link I found that might be useful to you:
http://www.peachpit.com/articles/article.aspx?p=759704&seqNum=2
 

Christine1234

macrumors regular
Original poster
Mar 2, 2011
161
10
Snowflake, AZ
Yikes! It's a 1.4 GHz PowerPc G4 from 2006. I didn't know not to wear a grounding wire, I always wear one when I stick my hands into a computer or any circuit. (I worked on circuit boards in research and development in the military at one time.)

This may be a little more of a hazard than I'd care to deal with. I do have other Macs that can be used, it's just that this the one I always use and it has everything on it. I'd have to get some software to get the other ones to accept all the files that are on this machine.
 

zen.state

macrumors 68020
Mar 13, 2005
2,181
8
You need a CRT discharge tool and can even easily make your own since it seems like you don't have one.

Taken from this page I have included the photo and info below but I encourage you to read that whole page.

"If you do not have a discharge tool, you can use an insulated screwdriver attached to a wire lead with alligator clips on both ends as shown here. You should also use this discharge method as a follow-up after using the older Apple CRT discharge tool to ensure that the CRT is discharged."

CRT Discharge Procedure Overview

These are the major steps for discharging a CRT:

1. Set up a CRT-safe electrical area.
2. Remove the housing.
3. Attach the discharge tool to the ground lug on a built-in monitor. Attach the discharge tool to the metal chassis on a stand-alone monitor.
4. Touch the discharge tool probe to the anode aperture.

CRT29.gif
 

Christine1234

macrumors regular
Original poster
Mar 2, 2011
161
10
Snowflake, AZ
I could easily make that tool, thanks. This project is starting to sound just a little intimidating with all that voltage.

I have a grape iMac G3 400 DV slot loading computer and just maxed out the RAM in it few months back. It's running Panther, but I picked up the retail disks for Tiger this week and can put that on it, then look around for Windows 2008 for Macs and put all the files from this machine on it. Then this eMac can sit for months and the voltage can dissapate before I open it up.

What do you think? Yes, I know they're older computers, but I love the old Macs.
 

zen.state

macrumors 68020
Mar 13, 2005
2,181
8
If you make that tool and use it properly and with the proper type of screw driver you can discharge the harmful buildup and then you could touch it all you wanted.

When you're intimidated and worried it's a lot easier to get hurt or do something wrong. Just relax and read up on it in that link I gave above. If there is anything at all you're unsure about just ask here and I will respond.

You can do it soldier! :)
 

zen.state

macrumors 68020
Mar 13, 2005
2,181
8
LOL, OK, as soon as I get the capacitors. :)

I cannot emphasize enough though how much you need to be sure you do everything 100% right. If I were you I would read the instructions at least 3 times and then visualize it in your mind before you do it. It may sound a bit anal but it will keep you safe to enjoy the rewards of your efforts.
 

Christine1234

macrumors regular
Original poster
Mar 2, 2011
161
10
Snowflake, AZ
I cannot emphasize enough though how much you need to be sure you do everything 100% right. If I were you I would read the instructions at least 3 times and then visualize it in your mind before you do it. It may sound a bit anal but it will keep you safe to enjoy the rewards of your efforts.
I plan to do just that, and probably read the instructions a few more times besides. :) I've worked on printed circuit boards and electronic equipment, but never on anything that had voltage on it at the time. Staying alive sounds pretty good, I'll be careful.
 

zen.state

macrumors 68020
Mar 13, 2005
2,181
8
I keep thinking of things.. damn sporadic mind.

Since it's not performing perfectly and you seem to have other Macs I would keep it unplugged and at least once a day press the power button with it still unplugged until the repair. This is a good extra precaution to have even less of a charge to discharge with that DIY tool.

Thats an official Apple repair document though so it's info and the DIY tool can be trusted.
 

Christine1234

macrumors regular
Original poster
Mar 2, 2011
161
10
Snowflake, AZ
OK, I just bought the set of capacitors on eBay. There are four sellers selling these sets specifically for the g4 eMacs, so this must be a common problem, like someone said. It gave a delivery date of by January 12th.

In the meantime, I have the RAM maxed out on that iMac g3. Should I put Tiger on it, or stick with Panther? I've heard Panther is more stable, but then other people have recommended Tiger. What do you think?
 
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