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Baking Tubes Procedure - Help...

Put the tubes in the oven with it cold.

Set oven for 175C and turn it on.

Let it run for 3 hours, turn it off and let it cool before opening the door.

This discolors Bakelite bases on octal tubes.

I believe Morgan Jones is credited with coming up with this procedure.

It is supposed to help activate the getter and remove residual gas in the tube.

I have experienced fewer problems with NOS tubes since I started doing this. Maybe it works, maybe it is just coincidence.
 
Being as closed minded and ignorant as I am, I can not see what this would achieve even with the premise of activating the getter by heating it to get rid of residual gases.

At 175 C for three hours is more like cooking an unstuffed turkey, but wouldn't that already be surpassed by just turning on your amp and powering up the tube and heaters and playing music through it for a good while? The barium getter would be right hot and more than ready to get every molecule of gas at running temp. All of this without risking damage to the base or envelope (mostly by being overly eager and playing hot potato with an 805 or a 12AX7).
 
Put the tubes in the oven with it cold.

Set oven for 175C and turn it on.

Let it run for 3 hours, turn it off and let it cool before opening the door.

This discolors Bakelite bases on octal tubes.

I believe Morgan Jones is credited with coming up with this procedure.

It is supposed to help activate the getter and remove residual gas in the tube.

I have experienced fewer problems with NOS tubes since I started doing this. Maybe it works, maybe it is just coincidence.
Thanks Bro, I appreciated it.
I just read someone do it with 130ºC for 3 hours;
Maybe I would start it with 100ºC for 3 hours with the small tubes, and next day up to 120ºC, unless best suggestion...
 
Put the tubes in the oven with it cold.

Set oven for 175C and turn it on.

Let it run for 3 hours, turn it off and let it cool before opening the door.

This discolors Bakelite bases on octal tubes.

I believe Morgan Jones is credited with coming up with this procedure.

It is supposed to help activate the getter and remove residual gas in the tube.


I have experienced fewer problems with NOS tubes since I started doing this. Maybe it works, maybe it is just coincidence.

How can one remove "Residual Gas" from a vacuum?
The heaters run at excess of 500 degrees Celcius, what is a domestic oven going to acheive?

What a load of rubbish!
 
If a tube develops a leak the getter (flash) will turn white even at room temperature. Thus, the getter is still active. It works long after it is flashed onto the inside glass.

Since reaction with residual gas is temperature dependent as most reactions are, heating the tube will accelerate this action.

The procedure is based on sound principals.
 
How can one remove "Residual Gas" from a vacuum?
The heaters run at excess of 500 degrees Celcius, what is a domestic oven going to acheive?

What a load of rubbish!
The getter is supposed to do it if it is hot.
After 6 month or so the getter goes to sleep and need to be reactivated before usage.

I do not like to use my amp as test pilot for NIB NOS tubes made in overseas about 30 years ago.
The tubes need to be heated before receive HV in a amp.
 
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If you take a look at the link supplied, it clearly states that the absolute vacumm is attained by an explosion within the valve using the getter to spray a Barium compound. Hence the mirrored effect on the inside of the envelope.

This action is a once only action and it caused electrically, without using heat!

http://www.vacuumstate.com/fileuploa...lves%20pix.pdf
 
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We want to believe....on one hand heating up the tubes will reactivate the getters but on the other hand the folks that sell tube collars will pitch keeping tubes cool is more Gooder. So in real life what's the application....tubes in console amps would be less gassy than tubes in guitar amps...why...in console amps the getter is activated because heat rises from the heaters to the getters but in guitar amps the tubes are up side down and the getters are the coolest part of the tubes... So put those gassy tubes either in an console amp or the oven.
 
Meltdown comes to mind here but an interesting concept.
I think, after over 50 years of valve gear repairing, that there is more than a jot of evidence that running the valves for a minute or so before putting power on the anodes keeps the cathodes in good condition and maximizes the life of the valve. (6L6, EL34, 2A3, KT88 etc). So maybe warming them up first will help.
 
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Just plug the tube in. When it is operating for a few hours, it will get hot enough for the getter to work well.
Baking tubes is just as stupid as "Cryogenically Treated Tubes".
Old NOS tubes accumulated gas over the years, and since these tubes left the factory in 1980s and came to my door it took a long road with many bumps and drops.

Which may let to the oxide cathode to loose some dust, that may cause a short circuit when receive the HV in usage, so baking the tubes may prevent it.
A tube broker is supposed to do it and charge alot for this service.