Little things that bug me

Doc B

Former President For Life
Staff member
Those are not "smoked glass tubes" that you are looking at on ebay. The opaque coating is Aquadag - Aqueous Deflocculated Acheson Graphite - colloidal graphite. It's there to reduce the emission of secondary electrons through the glass envelope, which are emitted when high energy primary electrons emitted from the cathode strike a metal part in the tube. 
 
Thanks Doc! This is really cool info that I was unaware of mainly because I only ever see "smoked glass" in the description of those tubes.
 
WHAT!!!???

I just paid some guy an extra $100 per tube to upgrade them to the smoke finish on the tubes I just bought!

Kidding, but yes I get annoyed with things like that too, especially when they come from the 'experts' selling them.  Good information.
 
Back
Top