Overdriving NO Tubes

"Boomer" wrote in message
...
I do not need to correct myself :-) and might add you have mis-read this
and misexplained
some things

I think it is more "Sorry Pszemol" please correct yourself : -)

"which is not true to my knowledge. They do get ionized and they
emit UV light, which is turned into visible rays of light by the phosphors
mixture on the internal surface of the tubes... "

Well, that is incorrect as the bulb does not generate enough energy to
ionize Argon. What
makes you think it does.Only HID generate enough energy to ionize Argon.
Do you have ref.
that states that Argon in fluro lamp gets ionized and produces light or
are you just
assuming that ?

"If you use UV-transparent glass
type to make the tube and do not use phosphors you would get the UV
fluorescent tube."

It is the Mercury that becomes vaporized and ionized that does that,
producing UV not
Argon. You will only see Argon peaks in HID bulbs.


"It is not the pressure which generates light. "

I never said pressure generates light, I said

"Increasing bulb
pressure alone increases output, as the argon gas pressure increases, due
to added heat
and overdrive"

and

"Gas pressure = more lumens / watt"


Know where did I say pressure produces light, I said pressure increases
output. A bulb
with no Argon gas, thus less pressure from heating and will have a lower
efficacy rating
than one with Argon. An Argon filled bulb would have a higher efficacy
than a non-Argon
filled bulb. The pressure reaches about 2-3 torr. Pressure lowers the
wattage required to
attain x lumens / W. Nowhere in the GTE manuals does it even mention that
Argon adds at
all to the spectrum and there is no Argon peak in any SED Curve

This is how things work;
When a fluro receives electrical current there is a passage of that
current through the
electrodes, called "Hot Electrodes", sealed at either end of the bulb. The
heat generated
heats up the tungsten filament and its emissive material such as Barium,
Strontium,
Calcium Oxide). As then become heated (950 C) they release electrons.
These electrons
travel at high speed from one electrode to another. Other electrons are
also released by
the field differences of the electrodes. This produces an electrical
discharge arch or
plasma. As these electrons and arch are produced it increases internal
pressure, causing
liquid Mercury in the tube to become heated, causing it to become
vaporized and shed
electrons. This release of electrons from Mercury produces UV light. These
electrons fall
back into orbit but only to be re-released again as the bulb is still
receiving current.
This "reaction" thus formed produces energy in the form of light and heat.
The light so
produced is UV at 253.7 nm. As this wave length hits the phosphors,
materials that are
capable of converting wavelengths from short UV to longer visible wave
lengths, there is a
change in the type of light. In other words these phosphors are excited to
fluorescence by
UV to the proper wave length.

Some known examples of phosphors and their colors

Cadmium Borate = Pink

Calcium Halophospahte = White

Calcium Silicate = Orange

Calcium Tungstate = Blue

Magnesium Tungstate = Bluish White

Strontium Halophosphate = Light Green

Zinc Silicate = Green


Please consult

GTE Sylvania Engineering Bulletin 0-341 (version 1 & 2 ), Fluorescent
Lamps, 22 pages



--
Boomer

Want to talk chemistry ? The Reef Chemistry Forum
http://www.reefcentral.com/vbulletin/index.php

Want to See More ?
Please Join Our Growing Membership
www.coralrealm.com

If You See Me Running You Better Catch-Up


Wow....