Coloured Fluorescent Lighting.

[Big_Spark]

Call me a****y retentive, but the correct spelling is

fluoresce

Simon..Fluorese is what things do under certain conditions, in this case the magnesium sulphate coating inside the glass tube. However if a substance or material is capable of this, then it is said to be Fluoresecent in nature, hence the term Fluorescent tube.

 

[funkydiver]

Another option might be to get the under car neonlighting kit and run it off a 12v step down transformer... ?? they come in red, green and blue...

I'd check to see if the step dwon is "acceptable" with a real electrician (FWL for example) first though... you get 2 x 36" neon tubes; 2 x 48" neon tube included in the kit...

FD

 

[breezer]

at that price it would be cheaper to buy a box of coloured flourescent lamps (well almost )

 

[funkydiver]

This is true, however, I was also thinking about the safety of having 240 volts at foot level (from what I can gather??)... the current off a 12v supply might not want to blow your socks off (literally )

FD

 

[breezer]

one slight problem, a flourescent tube has several thousand volts across it (all right i know only initally)

 

[funkydiver]

Apologies for my lack of knowledge... what's the difference between a neon and a flourescent??

This may well help the post, I'm not being bl**dy minded, I really don't know the difference...

FD

 

[breezer]

a "neon" is a tube filled with gas, neon is actually red (well it is when it lights up), different gases / combinations of gasses produce diferent colours, the tubes which contain the gas are bent into various shapes / letters like

flourescent tubes on the other hand are filled with a specific gas, that gives off ultra violet light, the INSIDE of the tube is powder coated and this powder actually glows or "flouresces" differnt colours of powders give the tube its colour.


both run on high voltage (we are talking thousands here) except that a flourescent tube only has a few thousnd volts to "strike" (INITIALLY LIGHT) after all it has to send a voltage anything from 2 - 8 feet (depending on tube) once "struck" the voltage / current is then reduced by the choke (which is what made the high voltage in the first place)

A neon sign on the other hand never "strikes" it is constantly sending a couple of thousand volts (at least) down the tube in order for it to work.

next time you see a neon sign have a look you will notice it is held away from its fixing and has thick insulation, this is because of the very high voltages in constant use, if it didn't it could easily arc and short to earth (or you)

you may be aware of "case modding" for computers they some times have a flourescent light in them, actually they don't its a "cold cathode" and i don't know how they work but perhaps FWL_Engineer can enlighten us (no punn intended)

 

[funkydiver]

Cheers breezer... I was beginning to think I wouldn't learn anything new today..

So a neon is not a good choice in this setting then??

FD

 

[breezer]

no, but i was just edditing my post to add about cold cathodes which is may be what you are thinking of / halfords supply

 

[securespark]

Jim. Just correcting Breezers spelling from a previous post. He was saying the uv tube makes things fluoresce, like white shirts etc..

 

[funkydiver]

expand my knowledge more... cold cathode??

 

[AdamW]

Well, the differences between a cold-cathode and a fluorescent tube are quite simple.

Whereas a fluorescent tube relies on thermionic emission, and thus has a heated cathode, a cold-cathode tube doesn't.

In fact, a neon tube is a cold-cathode tube. You can get cold-cathode discharge tubes with a phosphor coating (like fluorescent tubes do) but they don't all have it. Dunno why they have come to be known as cold-cathodes in computer modding circles... perhaps it is just because it sounds a bit cooler!

 

[funkydiver]

Whereas a fluorescent tube relies on thermionic emission, and thus has a heated cathode, a cold-cathode tube doesn't.

I take it this means that it needs the heat of a "spark" to get them jiggering enough to produce light??

 

[kendor]

A neon sign on the other hand never "strikes" it is constantly sending a couple of thousand volts (at least) down the tube in order for it to work.

next time you see a neon sign have a look you will notice it is held away from its fixing and has thick insulation, this is because of the very high voltages in constant use, if it didn't it could easily arc and short to earth (or you)

you may be aware of "case modding" for computers they some times have a flourescent light in them, actually they don't its a "cold cathode" and i don't know how they work but perhaps FWL_Engineer can enlighten us (no punn intended)

There are neon invertors out there(Masonlite are one supplier) which work on about 3-4Kv but are designed to run at a high frequency these are considered safer compared to the "High Voltage" types as if you were to touch the HT lead you would receive a burn /nasty tingle as opposed to a possible lethal shock and are approved for neon signs that do not need to be "kept out of access /reach" although it is still good practice to mechanically protect the glass from breakage, insulating boots and posts must still be used though. You will also be able to dim/flash the neon if the right invertor is bought. must admit neon looks very sexy around the house if used with taste.
Masonlite Ltd
36 Second Avenue
Chatham
Kent
ME4 5AX
Tel: 01634812751
Fax: 01634811883
Web:
Email: [email protected]

 

[kendor]

the colour of the gas whether it be argon, neon or whatever isn't the reason for the different colours(there are clear non coated tubes if you wish just to see the colour that the gas will transmit) you can have blue gas but a totally different colour from the tube the coating on the inside of the tube is chosen for it's particular wavelength properties and this alteration of the wavelength is what gives the intended coloured light output.
The receptors in the eye are sensitive to certain wavelengths of light and the brain interprets this as different colours that is why some light is invisible to the eye.