Apple Display Monitor 21 Inch (Old CRT from 98?)

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Apple Display Monitor 21 Inch (Old CRT from 98?)

Hey everyone

I have this old apple monitor. A picture and description can be found at this ebay listing http://cgi.ebay.com/Apple-Studio-Display-21-Inch-Blueberry-Monitor-Display_W0QQi temZ150054490363QQihZ005QQcategoryZ81686QQrdZ1QQcmdZViewItem?hash=item1500544903 63

Anyway, here's what happens with it...the power light on the front goes on. When the cable is connected to a computer, the power light will go amber when the computer is off and green when the computer is turned on-but no picture will come up. I've tried to increase the brightness and contrast to no avail. Last night when I connected it to a G4, I heard that "sizzle" that CRT monitors make for a second, but then it stopped again-still no picture. The USB ports on it work and it appears to be well taken care of. Anyone have any idea what could be wrong with it? Any ideas on a parts supplier? Any websites with info on how to fix it yourself-or is that even possible?

Thanks for any help in advance.

PS-If your idea is to get a new monitor please don't bother-I'm not in a financial place to afford one-especially one of this caliber.

Apple Studio Display 21 Inch

Posted on Nov 6, 2006 1:56 PM

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Answer 1

BSteely

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Nov 6, 2006 7:14 PM in response to LateNiteNate

Can you see a faint orange glow in the CRT's electron gun? This would be at the extreme opposite end from the screen. A CRT is like an old vacuum tube and you should see the glow of the heater element. If there is no glow, it could be that the heater element's power supply output has failed. That can be fixed but it could be a difficult self-repair.

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Answer 2

LateNiteNate Author

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Nov 6, 2006 11:34 PM in response to BSteely

I'm not exactly sure where to be looking for this but when I checked it with the lights off I didn't really see any glow...but again, I'm not sure where to be focusing. My best guess is that there is no glow-and if this is the case, do you have any information on where parts for such a thing would be available? I have a friend who's good with soldering and small electronics but not great at troubleshooting before fixing.

Thanks for taking the time to reply!

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Answer 3

Nov 7, 2006 1:35 AM in response to LateNiteNate

Was the it working with your current hookup, then failed, or is this the first time you have tried it with this computer? If it is the first time, how is it connected? For example if the computer has an ADC port and you use the ADC to DVI adapter followed by a DVI to VGA adapter, it won't work. You would need the ADC to VGA adapter.

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Answer 4

BSteely

Level 5

7,643 points

Nov 7, 2006 3:48 AM in response to Malcolm Rayfield

I agree with Malcolm. It was silly of me to jump straight to the conclusion that the CRT heater may be out when there are so many other things to know and check first. I don't know why I jumped to such an early conclusion.

What is the history of this monitor? Has it ever worked for you? When was the last time it worked (when did it fail)? Did you just buy it off of ebay and you're trying it for the first time? In that case, did the seller say it worked or not? And per Malcolm, how do you have it hooked up? Is it possible for you to try it connected to other Macs in case the problem lies not with the monitor but with the Mac it is connected to?

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Answer 5

LateNiteNate Author

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Nov 7, 2006 9:35 PM in response to LateNiteNate

Hi again...

Ok I checked again today-no glow whatsoever.

I have never had the monitor working. I've had it hooked to a PC and that didn't work and I've had it hooked to a known good computer (a G4) and it didn't work with that either...this particular computer that I tried hooking it up to has a very similiar monitor already connected to it, just a much smaller version. I have no idea on the history of the monitor, it was given to me by someone who thought I might make use of it.

I know this isn't too helpful, sorry I don't know more about it.

When the monitor is plugged in but not attached to a computer, does it say no signal or anything like that? Because no matter what, NOTHING appears on the screen.

Let me know if there is any more information I could provide in troubleshooting this and, as always, thank you for the help.

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Answer 6

BSteely

Level 5

7,643 points

Nov 8, 2006 8:06 PM in response to LateNiteNate

Well if the heater doesn't heat up the cathode, you are never going to see anything on the screen because the electron gun that shoots at the back side of the screen to light up the phosphor isn't going to be working.

Do I understand you correctly that you have another, albeit smaller, Apple CRT monitor with a clear case? Can you see the heater glow on that one in a totally darkened room? If not, maybe I am not correct to say that the glow should be showing up. It might be covered up by the metal can that goes over the video amplifier board plugged onto the very back of the CRT's neck.

I mentioned fixing this would be a difficult self-repair. I wasn't kidding about that. You would need to locate a broken down spare monitor to canibalize for the parts you need. It would be far easier to do a whole board swap than to try and troubleshoot the failed power supply without any schematic or access to the required damaged parts.

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Answer 7

LateNiteNate Author

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Dec 10, 2006 10:29 AM in response to LateNiteNate

Hello again...I apologize for the extreme delay in posting.

Today I took apart the **** monitor finally to see if I could find anything that looks out of place. The heater element mentioned before DOES indeed glow orange. I can see that light now with the case off. I did notice this one cord that doesn't connect anywhere. It goes from a metallic foil like line that follows along the back of the screen and it has an eyehole that appears to connect somewhere with a screw-I'm assuming it went on the bottom or top of this long brass tube that a screw fit into before I unscrewed it. I'm not sure if it is just a grounding wire or if it is something more important. The monitor still turns on and will go orange and green depending on the computer being on or off but I still see no picture. I noticed many little dials and knobs around the monitor as well-can these be adjusted?

Any continuing help would be appreciate and I can provide pictures if need be. Just let me know. And of course thanks for all the help!

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Answer 8

Dec 10, 2006 5:07 PM in response to LateNiteNate

Be very careful with the case open. You can get a very nasty shock, even it it has been unplugged for a while. The back of a CRT is delicate. Hit it wrong and you have shards of glass flying everywhere. Safety goggles would be a good idea.

The loose wire might mean somebody had it apart to fix it before.

Don't turn any of the adjustments. They will not help if you have no picture, and will be hard to get back to the correct settings if you do get it working. Wrong settings can cause damage or X-ray emission.

If you don't have a service manual, and the right tools and test equipment, you should carefully put the case back on, and try and fine a place that services computer displays.

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Answer 9

LateNiteNate Author

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Dec 12, 2006 4:51 PM in response to LateNiteNate

Yeah...I even went so far as to plug it in while the case was off and goof around with it. Call me intelligent. Thanks to everyone who tried to help me fix it, I appreciate your time. I think I'm gonna go take a sledgehammer to it now.

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Answer 10

Dec 13, 2006 6:52 PM in response to LateNiteNate

I think that sounds like the best idea.

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