17" CRT monitor snaps and flickers

Question

Level 1

10 points

17" CRT monitor snaps and flickers

For the past week or so, when I've been using my G4 mac, the 17" CRT would periodically make a soft snap followed by the display pulsing (image getting bigger, then smaller, then settling out). The other day, I booted up the computer, and the monitor had a very brief, white flash on screen along with a VERY loud SNAP. The sound was pretty much like a party popper that shots confetti when you pull a string. Anyway, the power light on the screen would be green, but the monitor was black. All subsequent reboot attempts led to the same SNAP followed by a very dim image that would fade to black. What is going on with my screen???

G4, Mac OS X (10.3.x), it's used

Posted on Feb 14, 2009 3:55 PM

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Answer 1

japamac

Level 7

24,400 points

Feb 14, 2009 5:47 PM in response to Skinavish

What is going on with my screen???

It wants to be let go.
"Move on" it 's saying, and "remember our good times, 'cause i'm a gonner".......

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Answer 2

Feb 14, 2009 7:03 PM in response to Skinavish

Here Lies Skinavish's
17" CRT Monitor
May It RIP

Cheers, Tom 😉

P.S. Now you have a good excuse to buy an LCD flat screen monitor.

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Answer 3

Skinavish Author

Level 1

10 points

Feb 15, 2009 5:58 PM in response to Texas Mac Man

How will an LCD work? My g4 has the power plug for the monitor kind of attatched to the computer itself(rather than a wall socket). Will an LCD still work?

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Answer 4

Feb 15, 2009 7:20 PM in response to Skinavish

What model G4 do you have?

Plugging the monitor power plug into the Mac is for convenience only so that when the Mac is shut down, the monitor is also shut down. You can plug a monitor onto a separate outlet. You should have a separate video signal cable connected to the Mac.

 Ckleers, Tom 😉

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Answer 5

Feb 15, 2009 8:04 PM in response to japamac

The snapping sound is caused by arcing, often at the flyback transformer. That is the component inside the CRT that generates about 50,000 Volts to run the electron beam in the color tube. Sometimes dust accumulates near it, and causes it to arc. Sometimes it is dead already and is will just take a while to fall down.

Opening the CRT enclosure requires special training. The 50,000 Volts can linger for months inside the tube, the Flyback transformer, and the Big Red Wire. If you connect that 50,000 across your heart (e.g., hand-to-hand) it can stop your heart.

A flat panel display would really look nice on your desk.

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Answer 6

Skinavish Author

Level 1

10 points

Feb 16, 2009 1:39 PM in response to Skinavish

Thanks, guys! I just went to Fry's Electronics and am now the proud owner of an Acer 19" LCD flat panel. It works perfectly!

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Answer 7

direwolf8

Level 4

1,286 points

Feb 17, 2009 12:00 PM in response to Grant Bennet-Alder

It really shouldn't be more than 20,000 volts or so. If it's running 50,000 volts unplug it right away and step well back from the CRT, as it will be emitting x-rays.

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