Black Nixie Tube
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
- sprite
- Posts: 2
- Joined: Sun Oct 04, 2015 4:21 pm
Black Nixie Tube
My Nixie tube is black/burned on the back. Is this normal or do I need a replacement? Don't want to solder it to the board until I know if I need to replace it or not.
- Attachments
-
- nixon-tube.png (668.58 KiB) Viewed 749 times
- cconradd
- Posts: 11
- Joined: Thu Oct 01, 2015 11:21 am
Re: Black Nixie Tube
Normal.
I also wondered this at first but after some googling it appears they all look this way.
I also wondered this at first but after some googling it appears they all look this way.
- jarchie
- Posts: 615
- Joined: Sun Jun 24, 2012 2:16 pm
Re: Black Nixie Tube
The black spot is actually an important part of the tube design. Vacuum tubes require an almost perfect vacuum, but removing all gas is nearly impossible. Even worse, the tube walls and other components release absorbed gas long after manufacture. The black spot, called a "getter," is added during manufacture. The getter is composed of reactive material that binds gas. So the black spot is effectively a chemical vacuum pump and is active for the life of the tube.
Please be positive and constructive with your questions and comments.