From: SFPhysics@aol.com
Date: Mon Oct 25 1999 - 21:33:41 PDT
From: SFPhysics@aol.com Message-ID: <0.bb59d0a9.25468925@aol.com> Date: Tue, 26 Oct 1999 00:33:41 EDT Subject: Cheap cheap cheap DVMs & UV=blacklight
Harbor Freight Tools has the absolute lowest price on some surprisingly
accurate Digital Volt Multimeters! I have bought a set for as little as
$5.99 each and then calibrated them against an expen$ive digital meter. They
were all close enough to where I did not have to tag the meters with
correction numbers. They have a sidewalk sale twice a year with these in a
big bin.
Now about UV from a computer monitor. The cathode ray tube that you look at
will give off very low level "soft" X-rays (that's why your mother who
graduated from Cal Tech told you not to sit too close to the TV). In modern
tubes the glass is doped with lead and other elements to keep the exposure
rate to the operator very low. The UV component is almost negligible as the
electrons hitting the tubes "phosphors" put out most of their energy in the
visible spectrum. You will get much greater exposure from the classroom
fluorescent lights with their Argon/Mercury mixture! In fact, people who are
on certain medications must stay away from sunlight and fluorescent lighting.
Somewhere I have a UV meter sitting gathering dust. Next time I uncover it
(my storage system is essentially a geological strata system), I am going to
go over every monitor I can find and see what, if any, levels I can detect.
It is more sensitive than the beads, etc.. I would only worry if I found
that the front and back of my shirts were different shades where the monitor
bleached out the front like sunlight does to carpets, stained furniture, auto
upholstery, etc., or that my knuckles were getting sunburned while I typed on
the keyboard. ;-)
Best wishes to all on the list,
Al Sefl
Guaranteed to be correct 50% of the time!
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