What the purpose of putting radio active metals in tubes or ...

Quote from: GlennSprigg on August 31, , 12:55:48 pm

Basically, 'Thoriated' Tungsten vastly improved the Electron Emissions from Cathodes. (A given ).
However, for the supporters of Conventional Current flow, I guess it vastly improved the ABSORPTION
of electrons, or did something 'magical' to the Positrons that REALLY flowed from the Anode...   

I thought this was due to properties of thorium which do not rely on radioactivity and more with emissivity, so a unhappy match by physics to a nasty metal (obviously you are in deep shit with mother nature if you need to use radioactive materials in a god damn radio amplifier)

https://en.wikipedia.org/wiki/Hot_cathode#Thoriated_filaments

they are also used in old coleman lanterns (but I think now they use some kind of cerium ). It seems to require a plasma to function in a lantern, you will not get the brightness from electrically heating it, as I learned from this forum to my displeasure (complicated physics). It is not just a heat to light converter that functions in the presence of a plasma either, I think it needs to have 'flow' and some how depletes it.

https://en.wikipedia.org/wiki/Candoluminescence

It's probably some how related to the electrical effect? (maybe why they thought to try to use it)

The characteristics of thorium  that are used in these applications are not primarily to do with their radioactivity, as there are other materials which have similar properties, but have little or no radioactive content.
Thorium was used, because it works better-- that's all.

Indirectly heated tubes may or may not use thorium oxide in their "oxide coated cathodes" (most likely, not!).
In any case, the quantity is miniscule---- the probability  of damage from the radiation from such cathodes is vanishingly small from listening to a tube radio.

Large transmitting tubes use "thoriated tungsten", where the filament material is an alloy of thorium &  tungsten.
By a mechanism described in the Wiki you linked previously, the thorium component becomes concentrated at the surface, improving the ability of the filiament to emit electrons.

Obviously, these are larger elements, so there would be more possibility of radiation.
Most high powered Transmitting tubes have an external anode, which makes up most of the structure of the tube.
Any radiation has to make its way through these massive structures, then through the metal of the transmitter cabinet  & so on.

We need a "reality check" when we start worrying about peripheral radiation sources like this.

People work daily with such delights as Cyanide, which  has a "half life of infinity"-------it will always be just as poisonous as it is now!
Another thing is Phosphoric Acid --- a lot will burn you alive, a little bit is great for  killing rust.

We used to make teeth fillings with Mercury amalgam ----How many people died from that?

People used coal fires to get warm for many years---burning coal releases radioactve products, to say nothing of the several kW of Electromagnetic radiation  in the form of heat!

The characteristics of thorium that are used in these applications are not primarily to do with their radioactivity, as there are other materials which have similar properties, but have little or no radioactive content.Thorium was used, because it works better-- that's all.Indirectly heated tubes may or may not use thorium oxide in their "oxide coated cathodes" (most likely, not!).In any case, the quantity is miniscule---- the probability of damage from the radiation from such cathodes is vanishingly small from listening to a tube radio.Large transmitting tubes use "thoriated tungsten", where the filament material is an alloy of thorium & tungsten.By a mechanism described in the Wiki you linked previously, the thorium component becomes concentrated at the surface, improving the ability of the filiament to emit electrons.Obviously, these are larger elements, so there would be more possibility of radiation.Most high powered Transmitting tubes have an external anode, which makes up most of the structure of the tube.Any radiation has to make its way through these massive structures, then through the metal of the transmitter cabinet & so on.We need a "reality check" when we start worrying about peripheral radiation sources like this.People work daily with such delights as Cyanide, which has a "half life of infinity"-------it will always be just as poisonous as it is now!Another thing is Phosphoric Acid --- a lot will burn you alive, a little bit is great for killing rust.We used to make teeth fillings with Mercury amalgam ----How many people died from that?People used coal fires to get warm for many years---burning coal releases radioactve products, to say nothing of the several kW of Electromagnetic radiation in the form of heat!

For more information, please visit Tungsten Tube.

Currently, Tungsten has become a popular metal choice in use in many different types of jewelry. Tungsten carbide has an advantage over gold and silver, which is that it does not scratch very easily. Tungsten is one of the hardest substances on earth, which makes it a metal that could be used for various things. Aside from rings, the tungsten metal is used for many other products used in our lives.

For example, tungsten filaments are used as heating elements for electrical furnaces. Tungsten has a very high melting point (6,152 degrees Fahrenheit), which means that it can withstand high heat for long periods of time. Because of this heat resistance, tungsten is ideal for use in a furnace. For that reason, tungsten is often also used as heat shielding in furnaces to protect more fragile parts from being damaged.

The company is the world’s best Titanium Square Tubing supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

In addition to use in furnaces, tungsten metal is also used in electronics for the same characteristics as it is used in other products. Very thin tungsten filaments are used for electron emitters. In fact, tungsten is the metal that is used almost exclusively for that purpose. The tungsten filaments in these products and devices form terminals called cathodes. These electron emitters are used in in such thing as microwaves, X-ray tubes, and the cathode ray tubes found in computer monitors and television sets. Cathodes are negatively charged electrodes.

The way cathodes work is that as electric currents pass through the cathode, the tungsten filament begins to heat up. When the tungsten heats up and emits electrons. The electrons that are emitted create the images we see on our television or computer monitors. In addition, the heated electrons help generate the microwaves that so easily and conveniently heat up food in microwave ovens.

Life without your tungsten rings would be manageable. True, you could easily get a gold or silver ring. However, you would miss out on the benefits of tungsten&#;s characteristics that make it a very popular choice in wedding bands and other jewelry. While we could do without the tungsten based jewelry, it would be extremely difficult to imagine life without a microwave oven, television, or a computer screen. These products have become a part of our normal lives and we have grown extremely accustomed to use them. If it were not for the development of tungsten as a metal to use as a durable filament, our lives would be drastically different.

If you are looking for more details, kindly visit Tungsten Carbide Ball Price.