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krw[_3_]

In article ,
says...
On Sat, 5 Apr 2008 09:47:53 -0700, "William Sommerwerck"
wrote:

When I was young (and stupid), I took some sealed Polaroid ASA 3000
speed "film" sheets, attached some coins to the surface, and plastered
them all over a late 1960's vintage color TV, where I was working.
After running the TV all day, I developed the pictures, and found a
noticeable lightening around the coins. (Polaroid "film" is positive
exposure, not negative). The shadow wasn't very distinct. The "film"
on the front screen was barely exposed, while the "film" near the Hi-V
cable was more noticeable. The "film" had to be attached to the CRT
to get any kind of exposure. Those on the cabinet showed no shadows.
About the only change that this prompted in my lifestyle was to not
leave my loaded film camera on top of the TV set.

My memory (which might very well be wrong) was that one of the principal
sources of X-rays was the HV rectifier. GE got into trouble over excessive
X-radiation from their HV rectifier -- though the tube was situated such
that the kids would have had to stick their feet under the set (!!!) to
receive any significant dosage.

The principal source of X-ray emissions on a CRT is from the electrons
hitting the slot mask immediately behind the phosphor screen face, as
well as electron impacts on the phosphors themselves..

"Principal"? Two wrongs in one word.

X-rays are exhibited whenever an electron strikes a metal surface.

Whenever? Riiggghhtt, Dimbulb.

With things like a welding arc, it is barely measurable and considered
negligible. A TV screen, however, is thousands of "arcs" at one time. It
is still fairly negligible, however.

No, HV power supplies, even those intended for use as an anode supply,
do not emit X-rays.

AlwaysWring strikes again!

--
Keith