[ChrisG90]

Hi, I just bought my very first flat screen LCD that replaces an older CRT. After using it for a few days I've noticed I've become quite sensible and irritated when viewing it (headache for example). The very same irritation and headache location was attributed with the use of an older type glass CRT computer monitor. After I've replaced it with an LCD Monitor, the symptoms went away immediately.


Any gurus out there that know how these TV's function? I did some online research and found out about EMF field and how LCD's should not have any (or much less) of it compared to CRT technology. After that, I've used a Gauss meter only to realize that the new tv's EMF readings were quite normal and not an issue. After some more testing, while the TV is on, on the back side, right in the center there is a place that emits Radio or Microwave radiation that's quite high. I can't tell whether is radio or microwave radiation since the meter is kind of limited. It's constantly fluctuating while tv's powered on and even after it's powered off, the signal spikes at maximum for 20-30 seconds afterward, then disappears completely.

Signal pattern is different than that of a WiFi connection or wireless phone but more similar to the one of a cell phone while attempting to make a call or transmitting data over EDGE or 3G.

The TV doesn't have a wifi connection or anything like that, at least that I know of.

TV is a Toshiba 46XV645U. I'd really hate to return it just for this reason, the image quality is phenomenal.


I'd visited some folks and tested their TV's as well. Turns out a Sony 40V5100 has the very same signal pattern yet a Toshiba 40RV525R does not. A Samsung 40B6000 LED doesn't have it as well.


Any ideas are more than welcome,

Chris

 

[johnpost]

any radio or tv produces radio waves inside of it or very close to it.


if you are close enough to be affected by radio waves from the device then you are way too close.


lots of headaches are caused by poor posture, trying to focus your eyes on something and irritating tv shows. sit up straight, try some glasses, don't watch irritating shows.


some people were bothered by older computer monitors that had a slower refresh. modern computer monitors and tv doesn't have that problem.


viewing a computer monitor or a tv at a distance that your eyes can't easily focus on would lead to eyestrain or maybe headaches. sit at a distance you can focus on or consider glasses.

 

[Glimmie]

If the TV is brand new the plastics may be outgassing chemicals which your body chemistry is sensitive to. If this is the case it should only last for a week or two at the most.

 

[ChrisG90]

Don't have any difficulty viewing the screen at about 10 feet or so. Can rule the eye strain pretty much out also due to this TV being so easy on the eyes, with the CRT it had a little eye strain or had the effect it made the eyes tiered. With the Toshiba, I can watch it for a whole 2 hr movie and have relaxed vision afterward so to say

But you're totally right, eyestrain do cause headaches, valid point.


Glimmie might be on to something as well, it still does have some of that "new plastic" odor, especially if it's been powered on for a while.

Now, I need another tester of some kind

 

[degrub]

Do you have any fluorescent lights on while watching ? 60 cycle flicker might be a cause.

 

[DAP]

Old CRTs put out a 15 kHz audio wine. Most people don't notice it. I suppose some LCDs might also output some high frequency noise.


Audo and visual effects are far more likely than RF noise to cause headaches.

 

[smpowell]



Quote:
HDTV LCD - what kind of radiation is this?

Most likely low frequency "RF hash" from a power supply or some digital circuits in the TV. I suggest that you find a portable AM radio, tune it between stations, and turn the volume up so you hear static. Now wave the antenna end (usually the top) around your TV's "hot spot". Then wave the radio around any CFLs and other operating electronics (computer, dvd player, even calculators!).


"RF hash" is similar to the concept of static. Other than interfering with low frequency radio reception, it is harmless.

Quote:
I've become quite sensible and irritated when viewing it (headache for example). The very same irritation and headache location was attributed with the use of an older type glass CRT computer monitor.

I can think of several things that might cause your problem. Things that you can find with a gauss meter are not among them (I don't think much of the EMF "research").


1. Eye strain. It sounds like you have ruled this out.


2. Photosensitive Epilepsy - All TVs and computer monitors produce a flickering light. That’s because the video is actually a series of still pictures that are rapidly displayed on the screen. A small percentage of people are sensitive to this flickering. LCDs produce less flickering than CRTs. Read more at this links: https://www.efa.org/about/photosensitivity/ http://www.epilepsysociety.org.uk/Ab...sitiveepilepsy about how to minimize TV problems.


120 HZ LCD TVs should produce less of an effect than 60 HZ LCD TVs.


3. Ultrasonic Sound - Not too likely but, a problem with the TV might produce sounds that are at too high of a frequency for you to hear. However children & dogs could probably hear them. Loud sounds can cause problems even if they are too high a frequency to hear.

 

[eyager]

Are you watching TV in complete darkness without any room lighting? Are there any bright lights reflecting off the screen? Most TVs arrive from the factory in "torch mode" with the brightness/contrast and color controls maxed out. Torch mode might be good for sales, but its not so easy on the eyes, especially in a darkened room.

 

[ChrisG90]



Quote:
Originally Posted by degrub /forum/post/16846512


Do you have any fluorescent lights on while watching ? 60 cycle flicker might be a cause.

There are fluorescent lights in the vicinity yet don't notice any difference when they're on or off, but will test this possibility more profoundly, thanks!

Quote:
Originally Posted by DAP /forum/post/16847725


Old CRTs put out a 15 kHz audio wine. Most people don't notice it. I suppose some LCDs might also output some high frequency noise.


Audo and visual effects are far more likely than RF noise to cause headaches.

I'm quite familiar with that 15 kHz noise that was present in an older CRT TV I had, but it wasn't really bothering once being used to it. My previous CRT didn't had this noise.

Quote:
Originally Posted by smpowell /forum/post/16848898


Most likely low frequency "RF hash" from a power supply or some digital circuits in the TV. I suggest that you find a portable AM radio, tune it between stations, and turn the volume up so you hear static. Now wave the antenna end (usually the top) around your TV's "hot spot". Then wave the radio around any CFLs and other operating electronics (computer, dvd player, even calculators!).


"RF hash" is similar to the concept of static. Other than interfering with low frequency radio reception, it is harmless.




I can think of several things that might cause your problem. Things that you can find with a gauss meter are not among them (I don't think much of the EMF "research").


1. Eye strain. It sounds like you have ruled this out.


2. Photosensitive Epilepsy - All TVs and computer monitors produce a flickering light. That's because the video is actually a series of still pictures that are rapidly displayed on the screen. A small percentage of people are sensitive to this flickering. LCDs produce less flickering than CRTs. Read more at this links:

> about how to minimize TV problems.


120 HZ LCD TVs should produce less of an effect than 60 HZ LCD TVs.


3. Ultrasonic Sound - Not too likely but, a problem with the TV might produce sounds that are at too high of a frequency for you to hear. However children & dogs could probably hear them. Loud sounds can cause problems even if they are too high a frequency to hear.

You and DAP have raised an important issue that I have yet to completely check out: Audio! BTW, thanks for the explanation on #2, though I'm pretty content with strobes and light effects, I guess I should rule this one out as well?

However, on point 3, I believe there is something within the sound, ultrasonic as you put it, that bothers me somehow. I thank you both so much for almost pinpointing the problem since I just followed this idea and watched the TV without sound, on mute, and the effect or irritation is far less noticeable. I've played with the settings and down played every audio option and can't tell exactly what causes the problem that mimics the very same irritation that was found with the use of an old CRT monitor. I'll have to do some more tests and try new settings but for now, I'm pretty much off the gauss meter idea and RF sensibility

Quote:
Originally Posted by eyager /forum/post/16848904


Are you watching TV in complete darkness without any room lighting? Are there any bright lights reflecting off the screen? Most TVs arrive from the factory in "torch mode" with the brightness/contrast and color controls maxed out. Torch mode might be good for sales, but its not so easy on the eyes, especially in a darkened room.

While TV is on, there is plenty of ambient lighting around and none reflect off the screen... it better not, it's a matte screen

but have no problems with it, it's very. I just tried the "store" options as opposed to "home" and the TV like just you put it, it was like a flashlight

Right now it's around 'standard' setting, not very dim and not too bright.

 

[ChrisG90]

An update to this thread, it turns out the remote was the culprit. I somehow must be sensible to phosphorus or whatever material they use in the remote to make its buttons store light and illuminate in low light.


Duplicated the issue several times with the remote located at a safe distance, into another room: using it, almost immediately brings back the issues described in the first message.


I'm glad it's not the TV, it's been an amazing tv so far.