SOLVED CRT High Pitch Noise

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I've looked this up and some CRT monitors, when they emit a high-pitched noise (especially when you bring up an almost completely white screen) indicates something is deteriorating or somewhat detached from the inside of it.

Was going to ask is this an indication that's it's becoming more harmful to human health? I've read CRT monitors and TV's let out some level of radiation. The further back you go in time, the more harmful the CRTs are, but would this high-pitch be an indication that the CRT is possibly more harmful to be around now?
 
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HI MJOLNIR

Without positively knowing for sure the answer to your question: I'm going to say no, the noise is not related.

My personal opinion: DEATH TO CRT
Don't ask questions, just purchase an LCD (preferably an LCD with LED backlight) as soon as you can.
 

Ian

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Sometimes CRTs can also make a high pitch noise if they are operating out of spec (refresh rate too high). Although in relation to your question, I don't know if the noise/probelm would be more harmful to human health.

I agree with Clifford and would wholeheartedly suggest going for a quality LCD if you are in a position to.
 

Digerati

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It is likely the flyback transformer. It is used to control the electron beam in the CRT and operates at about 15.7KHz, which is near the high-end extreme of human hearing - at least for younger humans. It is a sign the monitor is beginning to fail, but there's no way to tell if that will be next month, or 2 or 3 years down the road. In the meantime, it is likely to keep dogs out of the room.
 
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High-end extreme in terms of high pitch, I take it? I mean, it doesn't bother my hearing I guess is what I'm trying to say.

Yeah, I'm replacing this, and giving it away. I'm just concerned for those I'm probably going to give it away to, if you know what I mean. Besides I'm looking to keep this as an antique so I was still just wondering if it's safe to use.
 

Digerati

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High-end extreme in terms of high pitch, I take it?
Yes, high frequency is what I should have said.

There's no danger from radiation or anything like that. CRTs emanating harmful death rays is just a myth. The high pitch noise is just an annoyance. The danger of CRTs is flying glass in the event of an implosion. Not likely unless you hit a baseball into it. And there is very high voltage (18,000+ volts) on the anode so I would not be sticking my hand inside the case without unplugging and properly discharging it first. And it would not be a good idea to lick the phosphorous off the inside of the tube. Other than that, besides dropping the heavy things on your toes, CRT monitors are perfectly safe and many still prefer their image quality over LCDs.
 
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Yeah they look awesome and I don't see how LCD's are necessarily better. On big screen LCD TV's sometimes they look blurry. Screw the guy who created the Death to CRT's article lol.
 

Digerati

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CRTs have several points against them. They weigh a ton. They take up lots of desktop real estate. They give off lots of heat. And they consume lots of power. And large screen CRTs, if you can find them, are very expensive.
 

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It is amazing to me, how many people don't think about energy consumption in this day and age. Think green folks!
 

Digerati

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Good point because not only do CRTs (and other less efficient devices) consume more power, they tend to generate more heat. That may be fine in the wintertime but in warmer months, that extra heat also puts greater demands on facility cooling.
 
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I have another question regarding CRTs.

So I understand that CRTs generally emit higher radiation and cause more stress/strain to the eyes than LCDs, for the most part. Right?

Also, are anti-glare filters for CRT monitors also radiation blockers? Because that's what I'm really after - something that can block radiation from by 1995 Sony Trinitron monitor, and prevent eye strain.

If the answer to the second question is yes, would someone say then that an anti-glare screen protector does the same thing? Could I simply buy that and have the same effect an anti-glare filter (the thing you place over the top of your monitor that looks like a window) would give?

Thanks for the help.
 

Nibiru2012

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So I understand that CRTs generally emit higher radiation and cause more stress/strain to the eyes than LCDs, for the most part. Right?
From Wikipedia:
Yes they do, CRTs can emit a small amount of X-ray radiation as a result of the electron beam's bombardment of the shadow mask/aperture grille and phosphors. The amount of radiation escaping the front of the monitor is widely considered unharmful. The Food and Drug Administration regulations in 21 C.F.R. 1020.10 are used to strictly limit, for instance, television receivers to 0.5 milliroentgens per hour (mR/h) (0.13 µC/(kg·h) or 36 pA/kg) at a distance of 5 cm (2 in) from any external surface; since 2007, most CRTs have emissions that fall well below this level.
So there's no need to worry, unless you're just paranoid. Anti-Glare protectors won't do thing for you in that regard protecting you from spurious radiation.

Regarding eye-strain, this will probably answer your question as it's really "flicker" that causes a lot of eye strain and headache issues. Again from Wikipedia:
Flicker

At low refresh rates (below 50 Hz), the periodic scanning of the display may produce an irritating flicker that some people perceive more easily than others, especially when viewed with peripheral vision. A high refresh rate (above 72 Hz) reduces the effect. Computer displays and televisions with CRTs driven by digital electronics often use refresh rates of 100 Hz or more to largely eliminate any perception of flicker

To Be Honest With You:
You're using antiquated technology, especially with a 1995 Sony Trinitron monitor. It won't last that much longer and LCD monitors cause far less eye strain and other issues. Their contrast and clarity have improved dramatically over the last few years and don't cause headaches, eye strain, etc. Get a good quality LCD LED backlit monitor.
 
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I'm looking to spend as much less money while having the necessities. I have an LCD TV, a laptop, and so forth but this CRT monitor will be used for this one other purpose (I have it so might as well put it to use).

I did searching on this trust me. I was just getting mixed up because while looking up anti-radiation filters for instance, I kept getting results about anti-glare filters and read what they are, one article saying they also block radiation so that's why I was just confirming here. I can get a filter like this for 10 - 40 dollars while and LCD monitor is typically around a 100 (I just want a screen I can look at but also won't stress my eyes or release radiation that would be harmful if I'm using the monitor for 6+ hours a day which I would need to do during the Fall semester).
 
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Do you have a problem with background lighting, reflecting off the monitor screen? If so, that would be the only reason I see, for purchasing the anti-glare screens. Anything else should be adjustable, through brightness and contrast as well as resolution settings.
 
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Well no that's not the issue. The issue is a combination of eyestrain/stress on the eyes, and radiation from the CRT monitor. I was just wondering if an anti-glare filter would block all of those, but I'm guessing now that it's not necessarily both (anti-glare and anti-radiation) as some sources seem to say. I think in order for it to be anti-radiation it must have that feature and, if it does, it comes with a "grounding" cable you plug in somewhere? I was confused when I read about that to be honest. Was this a power cable they were talking about? It apparently gives a filter the "anti-radiation" feature.

I can't really use anything other than my CRT monitor to study from so if anyone's wondering why I have to use it, that's why. Nothing else will be available to me then.

Edit Also here's where I read it:

"Some cathode ray tube (CRT) monitors also come with an anti-glare screen. If not, aftermarket anti-glare screens can be purchased that block not only glare, but also harmful ultra-violet (UV) radiation. Radiation is not a problem with LCD screens.

If you’d like an aftermarket anti-glare computer screen for your LCD monitor, these are also available. Many come in the form of a sheet of plastic that clings to the screen. These are also called anti-reflective screens and are designed to improve contrast and protect the display from scratches."
 
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Digerati

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So there's no need to worry, unless you're just paranoid.
Or the CRT monitor has bounced off the floor a couple times. ;) I supposed if you sat the CRT monitor in your lap for 10 hours a day for the next several years, the radiation might cause a problem, but not when sitting up on a desk.

There are many people who still prefer CRTs over LCDs. And many would argue the best CRTs are superior in picture quality than the best LCDs - especially for CAD/CAE work. But, there's no arguing the CRTs consume a lot more power and generate a lot of heat.
 
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Anti-Glare protectors won't do thing for you in that regard protecting you from spurious radiation.
Do you mean it wouldn't do anything, in that the radiation it would block (the very little amount) wouldn't make much of a difference in the end, or that it doesn't even block this trivial radiation?

It may not seem important to you but it does to me. Like I said, 6+ hours each and every day for an entire semester sitting rather close to the monitor to see what's on my screen, not to mention as earlier stated in this topic this CRT monitor's pretty used and seems to be falling apart (at least the transformer, or whatever that's failing is causing it to emit a high-pitched noise whenever there's a white-ish screen showing) and if anything this probably makes it less safer to use than before.
 
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TrainableMan

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Write to the company that made it, we would just be guessing as to how much specific radiation your CRT gives off.

According to this Article, they do make radiation filters that block 94%-99% of the radiation but I've never heard of it before reading this and I have never seen one. Maybe there is a slight chance someone will come along that has used one but I suspect you will have to research them yourself.

On the other hand this person from the Food & Drug Administration says they are perfectly safe in this Question/Answer post.
 
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I read both articles. I love how they contradict the heck out of each other.

Still I'm wondering though, if someone knows (doubt anyone does). Why is it that when I look up radiation filters for monitors (for CRT because that's mainly what people buy them for, since they are undoubtedly more likely to emit anything), I find more than half of results about anti-glare filters? That's why I asked if they're the same thing or do the same thing. Do anti-glare filters also happen to shield radiation and hence I found these in my search results?

Reading some comments on Amazon, I read at least two people say that in order to use the "anti-radiation" feature of some anti-glare filters being sold there, you first have to ground the "grounding cable" of the anti-glare filter. Someone please tell me what is meant by this, because all that comes to mind is a power cable. Just wondering if that's what they mean. Kind of doubting this is it though.

Edit: And in case one's wondering, that's why I ask almost any question here. It's almost ALWAYS about health. Sure some sources are saying don't worry even a bit about radiation from even old CRT monitors, but other just-as-credible sources say otherwise! I don't want to take a chance, and if there's something like anti-radiation filters that will solve this problem then wouldn't it be smart to just buy that instead of spending more money on an LCD, as opposed to tossing away an almost perfectly good CRT monitor? This is also the reason for my question is anti-glare filters providing anti-radiation features as well.
 
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TrainableMan

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Well I did have a glare filter at work years ago (but don't know anything about reducing radiation) and It's just a green wire attached to the filter. It does work exactly the same way as the third plug on an electrical cord. All you do is attach it to another wire (because it's too short) and run the wire to the metal screw that holds on the cover of an electrical outlet.
 
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