What's a Green Neon Lamp?

  • Thread starter Watson A.Name - "Watt Sun
  • Start date
I read in alt.binaries.schematics.electronic that Robert Baer
<robertbaer@earthlink.net> wrote (in <400CF540.A0990EA9@earthlink.net>)
about 'What's a Green Neon Lamp?', on Tue, 20 Jan 2004:
There *ARE* green neon bulbs, and they are called neon because they
use neon; no other gas.
The "magic" is the fact that the inner part of the glass envelope is
coated with...
...phosphor!
The blue and UV output from neon is pretty weak at normal current
densities. Green tubes containing just neon may have a short life due to
higher than normal current.
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
Interested in professional sound reinforcement and distribution? Then go to
http://www.isce.org.uk
PLEASE do NOT copy news posts to me by E-MAIL!
 
I read in alt.binaries.schematics.electronic that Robert Baer
<robertbaer@earthlink.net> wrote (in <400CF5B4.3B1DF153@earthlink.net>)
about 'What's a Green Neon Lamp?', on Tue, 20 Jan 2004:

No UV in the neon glow; the phosphor does the conversion.
It can't convert red light to green light! There must be light with
quanta more energetic than green ones to excite the phosphor. So, blue
or UV.

Anyone got a spectrum of an NE-2?
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
Interested in professional sound reinforcement and distribution? Then go to
http://www.isce.org.uk
PLEASE do NOT copy news posts to me by E-MAIL!
 
On Tue, 20 Jan 2004 10:34:30 GMT, the renowned Robert Baer
<robertbaer@earthlink.net> wrote:
No UV in the neon glow; the phosphor does the conversion.
The "neons" we got from Japan most certainly did not have neon fill.
Observed from the end, the glow was bluish, much like a discharge in
Argon gas. As well as green, we got ones with a blue phosphor. Quite a
treat in those days.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
On Tue, 20 Jan 2004 17:59:51 +0800, "Dave T." <417ci-ohc-v8@Perth.com.au>
wrote:

what purpose do they serve in the tuner? ive allways seen them there and
wondered.
Cheap surge protection coming down the antenna ?



Regards,

Boris Mohar

Got Knock? - see:
Viatrack Printed Circuit Designs http://www3.sympatico.ca/borism/
Aurora, Ontario
 
In article <8d+KRgCgSPDAFwVG@jmwa.demon.co.uk>,
jmw@jmwa.demon.contraspam.yuk mentioned...
I read in alt.binaries.schematics.electronic that Mark J.
127.0.0.1@?.?> wrote (in <75mdnU8DN8i3d5Hd4p2dnA@buckeye-express.com>)
about 'What's a Green Neon Lamp?', on Tue, 20 Jan 2004:

I'm sure this doesn't apply to NE-2 lamps, but in hard-sealed He-Ne laser
tubes, after a while the helium passivates

diffuses

right though the glass, and the
tube ceases to function because there is not enough helium inside to
initiate light amplification.

[snip]

Perhaps in these tubes, an element has migrated right through the glass,
rendering them useless?

They may have a striking voltage higher than 120 V. I'd want to try them
from a 250 V supply with a 220 kohm series resistor.
Well, the peak voltage of 120VRMS is 162V or something, so the
striking voltage must be higher than that. And I don't care what the
striking voltage is, they don't work in this app. The store sells
them as NE-2 lamps.


--
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Don't be ripped off by the big book dealers. Go to the URL
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Just when you thought you had all this figured out, the gov't
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@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
Watson A.Name - Watt Sun, Dark Remover wrote:

Well, two things. If it took years to get out od the glass, it will
take years to get back in, no? And if He gets out of a sealed glass
tube, what do you put it in that won't leak? I know for certain that
a balloon will let the He out in less than a day, so I'd say maybe a
half inch thick steel container? That's how it comes at the student
activities dept on our campus, where they throw a lot of parties and
inflate hundreds of balloons every few weeks. Man, it scares me to go
into that place, 'cause the helium tank is just standing there, and if
it fell over and the brass valve on top got broken off, it would jet
itself right thru the walls!

The partial pressure of the Helium in a HeNe laser is very small, so it
doesn't have any really great push to make it migrate through the glass.
But it does migrate through the glass. If you put the laser tube in a
bag full of He at 1ATM pressure, the pressure in the bag is drastically
higher than the partial pressure of the helium in the tube. The He
will start to migrate back into the tube. In about 1 to 2 weeks time,
there will be a normal load of He in the laser tube.

The He atom is so small, that it can pass through the intermolecular
spaces in just about any material.

Neon, on the other hand, is a big plump atom, and cannot pass through
the tiny intermolecular spaces in normal glass.

-Chuck Harris
 
In article <uCc+2sCoDQDAFwHJ@jmwa.demon.co.uk>,
jmw@jmwa.demon.contraspam.yuk mentioned...
I read in alt.binaries.schematics.electronic that Watson A. Name - Watt
Sun, Dark Remover <alondra101@hotmail.com> wrote (in <MPG.1a767ed8e785fc
d1989b60@news.dslextreme.com>) about 'What's a Green Neon Lamp?', on
Mon, 19 Jan 2004:

So I guess the best and most sensible thing to do
is just replace them with another NE-2 and hope it lasts another five
or more years.

Yes.

The old NE-2s that I'm taking out have turned almost
completely dark, and barely glow or don't glow at all.

You can increase the life by increasing the series resistance. The value
used originally is often set to 'get a nice bright light' rather than to
get long life and you may be able to go to double the value and still
get a stable discharge. If you get flickering, the resistance is too
big.
In the case of the reference oven lamp and the range indicator lamps,
the resistance is 56.2k, which is twice what I've seen for the usual
30k resistors used in pilot lamps. So the current isn't excessive in
either. The overcurrent indicator is 200k, so I can't go much higher
than that.

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
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goes directly to the trash unless you add NOSPAM in the
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Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
I read in alt.binaries.schematics.electronic that Boris Mohar
<borism@sympatico.ca> wrote (in <c8bq009tanupbnkoqm9vsbfq8tkkgm23a6@4ax.
com>) about 'What's a Green Neon Lamp?', on Tue, 20 Jan 2004:
On Tue, 20 Jan 2004 17:59:51 +0800, "Dave T." <417ci-ohc-v8@Perth.com.au
wrote:

what purpose do they serve in the tuner? ive allways seen them there and
wondered.

Cheap surge protection coming down the antenna ?
Yes. Those WW2 aircraft radios in black boxes (BC454?) had two or three
protecting different stages, IIRC. Or were some acting as g2 voltage
regulators?
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
Interested in professional sound reinforcement and distribution? Then go to
http://www.isce.org.uk
PLEASE do NOT copy news posts to me by E-MAIL!
 
"Watson A.Name - Watt Sun, Dark Remover" wrote:
Well, the peak voltage of 120VRMS is 162V or something, so the
striking voltage must be higher than that. And I don't care what the
striking voltage is, they don't work in this app. The store sells
them as NE-2 lamps.
Look at the glass, by the leads. The type number should be molded
into the glass.

--
We now return you to our normally scheduled programming.

Take a look at this little cutie! ;-)
http://home.earthlink.net/~mike.terrell/photos.html

Michael A. Terrell
Central Florida
 
Spehro Pefhany wrote:
On Tue, 20 Jan 2004 10:34:30 GMT, the renowned Robert Baer
robertbaer@earthlink.net> wrote:

No UV in the neon glow; the phosphor does the conversion.


The "neons" we got from Japan most certainly did not have neon fill.
Observed from the end, the glow was bluish, much like a discharge in
Argon gas. As well as green, we got ones with a blue phosphor. Quite a
treat in those days.
Many (if not most) "Neons" are actually Neon-Argon (although the mix
varies). I use them as a calibration source for spectroscopy. A few
strong yellow-red-orange lines dominate the spectrum. You might be able
to see some of the other lines using a CD (finally a use for AOL discs!)
as a diffraction grating in a dark room. I can only see the red orange
and yellow lines like this, but the neon I'm trying has an orange window
in front of it.

for a pretty picture of the lines (Java based simulation) try:
http://astro.u-strasbg.fr/~koppen/discharge/neon.html
or in text form:
http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/atspect2.html

The green neons I have seen are dimmer than the orange ones - I assumed
at the time they were just filtered - as you can see from the spectra,
this would work.

--
Chris
-----
Spamtrap in force: to email replace 127.0.0.1 with blueyonder.co.uk
 
Don Klipstein wrote:
In article <MPG.1a767ed8e785fcd1989b60@news.dslextreme.com>, Watson
A.Name - "Watt Sun, Dark Remover" wrote:


I need an indicator lamp that lasts as long as the rest of the
equipment that it's in, and runs off a hundred or so volts. And draws
ony a few hundred microamps. The problem is that these old PSes were
designed before LEDs were commonly available, so adapting the circuit
to use LEDs is _not_ easily done. The voltage is too high and the
current is too low. So I guess the best and most sensible thing to do
is just replace them with another NE-2 and hope it lasts another five
or more years. The old NE-2s that I'm taking out have turned almost
completely dark, and barely glow or don't glow at all. I guess that's
because they're on all the time, even when the equipment is turned
off. So a few years from now they'll have tens of thousands of hours
on them.

Get a better InGaN green LED, feed it with a fullwave bridge rectifier
that has a 220K or whatever resistor in series with one of the AC leads.
Be surprised at how much light you get with half a milliamp. Be
surprised with how much light you get at 1/4 milliamp (use a 470K
resistor).
Thanks for the info. I've run white LEDs off a couple hundred microamps
and they glow reasonably bright. Right now, I'm just happy to get the
NE-2 replaced in a couple places in two PSes, and as a pilot lite in
another couple PSes. The problem is that these are soldered in and it's
hard do get to them to unsolder the leads, in fact, the HP 6216 PSes are
so brittle that I'm afraid to pop the case off, for fear of shattering
it into splinters. The cases are *that* brittle.

- Don Klipstein (don@misty.com)

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
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In article <MPG.1a767ed8e785fcd1989b60@news.dslextreme.com>, Watson
A.Name - "Watt Sun, Dark Remover" wrote:

I need an indicator lamp that lasts as long as the rest of the
equipment that it's in, and runs off a hundred or so volts. And draws
ony a few hundred microamps. The problem is that these old PSes were
designed before LEDs were commonly available, so adapting the circuit
to use LEDs is _not_ easily done. The voltage is too high and the
current is too low. So I guess the best and most sensible thing to do
is just replace them with another NE-2 and hope it lasts another five
or more years. The old NE-2s that I'm taking out have turned almost
completely dark, and barely glow or don't glow at all. I guess that's
because they're on all the time, even when the equipment is turned
off. So a few years from now they'll have tens of thousands of hours
on them.
Get a better InGaN green LED, feed it with a fullwave bridge rectifier
that has a 220K or whatever resistor in series with one of the AC leads.
Be surprised at how much light you get with half a milliamp. Be
surprised with how much light you get at 1/4 milliamp (use a 470K
resistor).

- Don Klipstein (don@misty.com)
 
In article <MPG.1a76d06c23950806989b68@news.dslextreme.com>, Watson
A.Name - "Watt Sun, Dark Remover" wrote:
In article <uCc+2sCoDQDAFwHJ@jmwa.demon.co.uk>,
jmw@jmwa.demon.contraspam.yuk mentioned...

So I guess the best and most sensible thing to do
is just replace them with another NE-2 and hope it lasts another five
or more years.

Yes.

The old NE-2s that I'm taking out have turned almost
completely dark, and barely glow or don't glow at all.

You can increase the life by increasing the series resistance. The value
used originally is often set to 'get a nice bright light' rather than to
get long life and you may be able to go to double the value and still
get a stable discharge. If you get flickering, the resistance is too
big.

In the case of the reference oven lamp and the range indicator lamps,
the resistance is 56.2k, which is twice what I've seen for the usual
30k resistors used in pilot lamps. So the current isn't excessive in
either. The overcurrent indicator is 200k, so I can't go much higher
than that.
For really good aging, use the maximum resistor that reliably results
with the electrodes being fully covered or very nearly fully covered with
glow. Maybe go somewhat less for a little more brightness if this makes
the resistor really high.

NE-2 lamps want 150K-220K. NE-2H, which is different, is rated 20K or
25K hours with 33K and 5K hours with 22K (with 120 volts AC).

- Don Klipstein (don@misty.com)
 
In article <100p9v1iasrls4a@corp.supernews.com>, Oppie wrote:
The ones I've seen in pilot lamps are NE-2 style envelopes but are filled
instead with an argon mixture that glows blue and emits UV. the inside of
the tube is coated with a green phosphor.
Lumex is one manufacturer that comes to mind
http://www.lumex.com/pls/lumex/subproduct_galary?iproduct_id=1000656
Argon does not make significant amounts of that kind of UV... I think
it's a mixture with krypton or xenon. The krypton or xenon is a minority
ingredient in the mixture but that's the way it works best for producing
shortwave UV. The krypton or xenon (xenon works better) is usually mixed
with neon but I have seen argon used for that purpose.
It is easy for the neon-xenon mixture to glow with an argon-like color.

You will have to examine a spectrum of the glow to know what is actually
in there. Been there, done that.

- Don Klipstein (don@misty.com)
 
In article <75mdnU8DN8i3d5Hd4p2dnA@buckeye-express.com>, Mark J. wrote:
In news:MPG.1a767abb5210b607989b5f@news.dslextreme.com (Watson A.Name -
Watt Sun, Dark Remover):
In article <slrnc0orcs.l3v.don@manx.misty.com>, don@manx.misty.com
mentioned...
In article <MPG.1a75cf5230e4f007989b5a@news.dslextreme.com>, Watson
A.Name - "Watt Sun, Dark Remover" wrote:

I found some replacement lamps for the neon lamps that are in the HP
power supplies that I got off Ebay. They're distributed by Linrose,
the company that has those lousy LED displays at Fry's. I bought a
regular red neon for $3 something, but the green neon is about $5, and
obviously it's not neon because neon is red. So what gas is used in
those green ones?

Most green neon lamps have a mixture of neon and xenon, mostly neon.
But most of the radiation is of xenon wavelengths, mainly the 147 nm
very short wave ultraviolet line that is best obtained with low xenon
pressure. The bulb is coated on the inside with a phosphor that
fluoresces green from shortwave UV.

The mini green neon lamps in Radio Shack's green neon "cartridges"
have a neon-krypton mixture rather than a neon-xenon mixture.

- Don Klipstein (don@misty.com,
http://www.misty.com/~don/oddbulb.html)

Wow, thanks, Don. I went over to a local electronics store and asked
the guy at the counter if he had any NE-2 neon lamps. He went down
the aisle, and pulled out a box, and turned it upside down, and said
sorry, nothing in stock. Then he said, but there's some neon lamps
down there, in a big pile of stuff. I sorted thru handfuls of neon
lamps, most of them having a 100k resistor, and found some without, so
bought a half dozen of them.

I got home and pulled the power supply apart and unsoldered the old
one and installed one of the ones I bought. Turned it on, and
nothing. No light. So I said, I wonder of the others work? I got
out a suicide cord and a 47k resistor and alli clipped another one of
the ones I just bought and plugged it in. Nothing! Same for the
other four! I measured across them with the DMM and the full 116 or
so VAC was across each! And they didn't glow at all. Cheese! I got
screwed! They're all DOA! So I had to unsolder the one in the PS and
I scrounged up an old NE-2 from the junkbox and installed it in the
PS. I didn't notice if the crap on the shelves was marked AS-IS, so I
can't take it back for exchange. Dirty rats! What little I know
about statistics tells me that it is statistically improbable that I
could pull 5 or 6 of those out of a pile of good ones and get all bad
ones, in other words it is statistically probable that all or most of
them in the pile are bad.

Ya know, this is Deja Vu all over again. I've bought stuff in that
store before and had bought bad parts, one would think that I would've
learned my lesson by now. The crap is bad! Don't buy it! But no, I
did it again. I seldom go to that store, so I guess I've developed an
aversion to it. After you've stuck your hand in the fire, you kind of
develop an aversion to getting burned again. But no, I got burned
again. Oh, well. Maybe I'll go to Radio Scrap, where at least I can
take it back if it's bad.


I'm sure this doesn't apply to NE-2 lamps, but in hard-sealed He-Ne laser
tubes, after a while the helium passivates right though the glass, and the
tube ceases to function because there is not enough helium inside to
initiate light amplification.

The "quick fix" is to suspend the "old" tube in a bath of helium gas, and
the molecules will slowly migrate back thorough the glass and the tube will
start working again.

Perhaps in these tubes, an element has migrated right through the glass,
rendering them useless?
Possibly the clunkers were of a different design intended for 220-240V?
Maybe they had Krypton-85 or something else radioactive (and with a
limited half life) to help them start? Maybe they had imperfect seals and
air leaked in over the decades (I have seen a batch of glow lamps like
that and a batch of xenon flashtubes like that in an older electronics
surplus store).

Maybe they were the special design neon lamps from Kodak "Max"
one-time-use camera boards (or similar), and that one actually requires
something like 270 volts to light.

Maybe they were just bad or rejects.

- Don Klipstein (don@misty.com)
 
In article <MPG.1a7692da5b147bd9989b65@news.dslextreme.com>, Watson
A.Name - "Watt Sun, Dark Remover" wrote:
The "quick fix" is to suspend the "old" tube in a bath of helium gas,
and the molecules will slowly migrate back thorough the glass and the
tube will start working again.

Well, two things. If it took years to get out od the glass, it will
take years to get back in, no?
Since atmospheric pressure is in the ballpark of 100 times that of the
helium that was inside, it supposedly takes as little as weeks to restore
a HeNe laser tube that requires a "helium bath".

Well, there's no helium. But I've read that there's a small amount
of radioactive material in there to help start the breakdown at a low
voltage. If that poops out after a few dozen years, then the lamp
would breakdown at a much higher voltage. But the really old NE-2s I
pulled out of the junk box and hooked up worked fine after a few dozen
years!
True NE-2 has the "traditional" mixture of 99.5% neon .5% argon. I have
heard that in some lamps (other than NE-2) with this mixture, after enough
run time argon ions embed themselves into the glass and you get purer
neon. A neon lamp with pure neon sometimes requires favorable electrode
material, photoelectric effect, radioactive material, or whatever to start
on 120 VAC.

You can't replace argon by soaking a lamp in it the way I heard for
helium. At least the argon does not escape or get lost when the lamp is
not running.

- Don Klipstein (don@misty.com)
 
In article <400CF52D.C6BDE6DE@earthlink.net>, Robert Baer wrote:
"Watson A.Name - Watt Sun, Dark Remover" wrote:

You are incorrect on the "obviously".
There *ARE* green neon bulbs, and they are called neon because they
use neon; no other gas.
Neon does not make that kind of UV. Green neon lamps contain a mixture
of (usually) neon and xenon (Yes, I do know what the spectra of helium,
neon, argon, krypton, xenon, and glow lamps of all colors look like).
Xenon produces the shortwave UV, and does so best at a pressure of a
fraction of a mm Hg. Pure xenon won't strike at just a few hundred volts
or less, so they mix it with neon. The neon does not interfere much with
xenon doing the radiating since the energy levels in a xenon atom are
lower than those of a neon atom.

The "magic" is the fact that the inner part of the glass envelope is
coated with...
...phosphor!
True. And I have seen neon signs with pure neon and green-glowing
phosphor (in tubing labelled "green" even!). They glow orange, just a
little less red than pure neon in clear tubing. This is true at the ends
where negative/cathode glow (what you see in the smaller glow lamps)
exists as well as where there is a main discharge column. Pure neon does
not make enough shortwave UV to make a lamp with green-glowing phosphor
appear green.

- Don Klipstein (don@misty.com)
 
In article <400D4FFA.ACDBA830@earthlink.net>,
mike.terrell@earthlink.net mentioned...
"Watson A.Name - Watt Sun, Dark Remover" wrote:

Well, the peak voltage of 120VRMS is 162V or something, so the
striking voltage must be higher than that. And I don't care what the
striking voltage is, they don't work in this app. The store sells
them as NE-2 lamps.

Look at the glass, by the leads. The type number should be molded
into the glass.
Nothing on any of them, I checked with my 10X magnifier. On two of
them there was a smudge of a green dot next to one of the leads. I
wonder what that signifies.

Thanks.

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
In article <400d3052$0$15628$61fed72c@news.rcn.com>,
cfharris@erols.com mentioned...
Watson A.Name - Watt Sun, Dark Remover wrote:

Well, two things. If it took years to get out od the glass, it will
take years to get back in, no? And if He gets out of a sealed glass
tube, what do you put it in that won't leak? I know for certain that
a balloon will let the He out in less than a day, so I'd say maybe a
half inch thick steel container? That's how it comes at the student
activities dept on our campus, where they throw a lot of parties and
inflate hundreds of balloons every few weeks. Man, it scares me to go
into that place, 'cause the helium tank is just standing there, and if
it fell over and the brass valve on top got broken off, it would jet
itself right thru the walls!


The partial pressure of the Helium in a HeNe laser is very small, so it
doesn't have any really great push to make it migrate through the glass.
But it does migrate through the glass. If you put the laser tube in a
bag full of He at 1ATM pressure, the pressure in the bag is drastically
higher than the partial pressure of the helium in the tube. The He
will start to migrate back into the tube. In about 1 to 2 weeks time,
there will be a normal load of He in the laser tube.

The He atom is so small, that it can pass through the intermolecular
spaces in just about any material.

Neon, on the other hand, is a big plump atom, and cannot pass through
the tiny intermolecular spaces in normal glass.
Just what I like: big, plump atoms! My favorite is oxygen..

I've heard that helium at cryo temperatures creeps out of the vessel,
so it's a strange beast. But I didn't know about the HeNe laser
leaking. A friend of mine in high school wanted to make a HeNe laser
so bad he had the tubes blown out of glass and was working on getting
the brewster windows. But his mom was cleaning his bedroom and
smashed the glass. :-( Jeez, that was back when the only lasers were
HeNe, like the mid '60s, maybe. Lasers had been around only a few
years.

-Chuck Harris

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
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My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
I can attest to the fact that a typical xenon strobe lamp can produce a
great deal of ultraviolet- I used them to make UV strobe lights for
planetarium light shows. It also helps a lot that most people's eyes are
dark adjusted for the shows too.

Cheers!

Chip Shults
 

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