I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?

Thank you.







--
I hope this isn't a controversial leaning subject, I'm genuinely
curious/interested.

"John Doe" wrote in message
...
I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Don't worry about this ... no known danger.

"John Doe" wrote in message
...
I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?

Thank you.




I wouldn't worry about that, the radiation from a correctly functioning
monitor or TV should be within safe levels.

However I would worry about blocking vents, which could cause overheating
and premature failure, or the animal drooling or ****ing into the monitor,
which could be fatal to the monitor and potentially dangerous to the animal
.. I had a rather expensive TV for repair a few years back where a tomcat
decided to relieve himself into the top vents. The cat was OK but the TV was
a mess. Horrible, sticky, pungent and worst of all highly corrosive and
rather conductive gunk all over the electronics, and a few blown components.

Dave

I would also worry about cat or dog (assuming a normal range of movable
pets) hair getting thru the small vents and into the set, and
eventually causing some sort of failure. It would probably take a long
time, but I would worry about that before I would worry about any EMC
effects.

H. R. (Bob) Hofmann

"John Doe" wrote in message
...
I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?

Years ago when TV sets had tubes, some of the tubes in the high voltage
section would emitt x-rays. Even then the x-rays were usually beaming down
so you had to be under them to get very much radiation.

I would worry more about my monitor over heating because the vents were
blocked.

My cat used to park herself on top of my PC monitor as irt was nice and
warm (I'm not using an LCD display yet!) I was worried about
ventilation and cat hairs getting into the unit so, reluctantly, I put
a stop to it.
Cheers,
Roger
PS. Meow, meow... the mean old sod, it was nice up there! Snuffles.

Ralph Mowery wrote:
"John Doe" wrote in message
...

I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?


Years ago when TV sets had tubes, some of the tubes in the high voltage
section would emitt x-rays. Even then the x-rays were usually beaming down
so you had to be under them to get very much radiation.

I would worry more about my monitor over heating because the vents were
blocked.


Sorry, but the main source of x-rays was the picture tube itself.
Any device which employs 15000 or more volts, with electrons hitting
metal with that energy will produce x-rays.
Thats why lead bases front glass is used.
Even so I would keep small children not to close to a color TV.

In article ,
John Doe wrote:

I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?

Ionizing radiation in CRT monitors is generated within the CRT itself,
and most of it issues through the faceplate; that's why they're made of
heavily leaded glass, and are very thick.

There's very little risk, and anyway, animals (presumably a cat) have
such short lifetimes that any kind of radiation-induced damage just
won't have time to develop the way it *possibly* could in a human.

Far more likely, the animal will block airflow through the monitor
(they're never well cooled at best), and will limit *it's* lifetime.

Isaac

Sjouke Burry wrote:
Ralph Mowery wrote:

"John Doe" wrote in message
...

I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?


Years ago when TV sets had tubes, some of the tubes in the high voltage
section would emitt x-rays. Even then the x-rays were usually beaming
down
so you had to be under them to get very much radiation.

I would worry more about my monitor over heating because the vents were
blocked.


Sorry, but the main source of x-rays was the picture tube itself.
Any device which employs 15000 or more volts, with electrons hitting
metal with that energy will produce x-rays.
Thats why lead bases front glass is used.
Even so I would keep small children not to close to a color TV.


The HV rectifier tubes were known to produce small amounts of xrays,
unlike the CRT, they weren't made of leaded glass. They were generally
well enclosed in metal shields though.

"John Doe" bravely wrote to "All" (05 Jan 06 21:13:23)
--- on the heady topic of "Too close to a computer monitor?"

JD Subject: Too close to a computer monitor?
JD Xref: core-easynews sci.electronics.repair:354113

JD I'm wondering about radiation levels at close range to the
JD electronics of a computer monitor.

JD Specifically, I'm thinking about an animal lying on top of the
JD monitor vents when it's cold in the room (when monitor cooling is
JD not an issue).

JD Is there a significant difference in potentially destructive
JD radiation at that close range?

JD I vaguely recall hearing about some significant radiation at very
JD close range to specific components?


There is not enough voltage in a tv to produce significant X-rays.
Perhaps the strongest source of EM radiation is when the unit is first
turned on and the degauss circuit activates. Many times you may notice
that a lamp on the same circuit will flicker. When the unit is running
there is always a powerful radiation sweeping the area around it. Try
for example wearing some sensitive headphones and bringing your head
near the side of the unit and you will hear this field.

A*s*i*m*o*v

.... Dunno if we'll get that past the CSA und UL 'owever.

The unions in some of the European countries (Seden primarily) made
abig stink about this more than 10 years ago, asnd as a result
standards were written that limited the external magnetic fields.
There are two main sources of external fields, the x-rays from the
high-voltage accelerated electrons hitting the acquadag on the inside
of the tube and the shadow mask/screen on the front of the set, and the
magnetic fields caused by the deflection yoke. Newer sets have figured
out how to limit the external fields so you cat or dog or hamster or
ferret or whatever probably should not have ite life shortened by the
deflection fields. The x-rays in any solid-state set are produced
entirely within the CRT itself. If you want to check for x-rays, you
could contact someone at your local hospital to see if they have a
gizmo they use around their x-ray machines to measure leakage, or you
could expose a role of film in a plastic container to possible x-rays
by placing it whre the animal sleeps for a couple of hours and then
having it developed. If the film doesn't come back all clear,
indicating no exposure to x-rays, then you can start ot worry. I still
think the hair problem is the one to worry about.

H. R.(Bob) Hofmann

Sjouke Burry wrote:

Ralph Mowery wrote:
"John Doe" wrote in message
...

I'm wondering about radiation levels at close range to the
electronics of a computer monitor.

Specifically, I'm thinking about an animal lying on top of the
monitor vents when it's cold in the room (when monitor cooling is
not an issue).

Is there a significant difference in potentially destructive
radiation at that close range?

I vaguely recall hearing about some significant radiation at very
close range to specific components?


Years ago when TV sets had tubes, some of the tubes in the high voltage
section would emitt x-rays. Even then the x-rays were usually beaming
down so you had to be under them to get very much radiation.

I would worry more about my monitor over heating because the vents were
blocked.


Sorry, but the main source of x-rays was the picture tube itself.
Any device which employs 15000 or more volts, with electrons hitting
metal with that energy will produce x-rays.
Thats why lead bases front glass is used.
Even so I would keep small children not to close to a color TV.

They used to use diode valves (tubes) as rectifiers for the EHT, and these
could emit x-rays, when they were in the off-state, i.e. electrons hitting
the filament when reverse biased. I believe (but have never seem for
myself) that they also used beam triodes as shunt regulators to pull the
EHT down to a stable level. The envelopes of these valves were not very
thick. There are web pages explaining how to take x-ray pictures using
these valves, but I believe that they overdrive the valves beyond their
ratings in order to shorten the exposure times. The web pages mention that
you want to find an earlier version of the valves made before they started
worrying about x-rays and adding lead to the glass.

Chris