Re:IBM mainframe tube module part II: Powering up and using ...
by SAI_Peregrinus on Sunday January 14, 2018 @03:22PM
(#16146157)
It's interesting how supposedly identical tube models look rather different. Part of that is the getter depositing metal onto the top of the tube, and part of that is probably that some tubes with the same number could come in slightly different packages: different plate colors/sizes, different glass size, etc. So while it looks like the Trigger 1 and CF1/2 tubes have been swapped around they're probably correct. It's a bit like having parts in both TO-92 and TO-18 packages, for the same part.
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Re:IBM mainframe tube module part II: Powering up and using ...
by jacquesm on Sunday January 14, 2018 @06:27PM
(#16147205)
The metal deposition inside the tubes is to get rid of the last of the Oxygen. A bunch of Barium powder and an igniter would be placed in a small cup like construction inside the tube during manufacturing called a 'getter', firing the getter would vaporize the Barium which would then attach to the remaining Oxygen molecules and subsequently deposit on the inside of the glass, the largest and coolest surface.
Re:IBM mainframe tube module part II: Powering up and using ...
by SAI_Peregrinus on Monday January 15, 2018 @12:27AM
(#16148689)
Good note. I mentioned the getter but didn't explain it, I should probably have done so.
Re:IBM mainframe tube module part II: Powering up and using ...
by kens on Sunday January 14, 2018 @04:00PM
(#16146402)
Yes, I was convinced at first that the tubes were shuffled around. But after carefully checking the model numbers I found they were correct.
On the other hand, I studied a different tube module that had random tubes plugged into it. This caused me great confusion when trying to figure out how it worked. I assume someone had been using the tube module as a desk decoration, broke the old tubes, and plugged in random new tubes.