I dissected a dead tube. Pix.

[leadfootdriver]

It wasn't actually dead, but it went to a to a loud buzz. I think a cathode shorted to the grid. So I gutted it.

I've done this before, but this time I know a little bit more about tubes. I'd say at this point that the Mica's are real important in keeping everything in line, and secured. Loose Mica tolerances probably make for a microphonic tube.

The Mica material seems to be real crumbly and flakey. The Filament wire is a high tensile strength, with an insulating coating. The Cathode tubes are so tiny, it's amazing they can get the Filaments in there. The Grid wire is about .0015" thick and wound nearly as tight. Only a machine could do it perfect like that.

I bet that most failures are probably broken leads to the pins. The leads to the pins are very fine and within tight quarters. How would you like to work with these little pieces for 8-10-12 hours a day doing production?

http://home.comcast.net/~leadfootdriver/JJ1.JPG

http://home.comcast.net/~leadfootdriver/JJ2.JPG

http://home.comcast.net/~leadfootdriver/JJ3.JPG

http://home.comcast.net/~leadfootdriver/JJ4.JPG

http://home.comcast.net/~leadfootdriver/JJ5.JPG

http://home.comcast.net/~leadfootdriver/JJ6.JPG

http://home.comcast.net/~leadfootdriver/JJ7.JPG

http://home.comcast.net/~leadfootdriver/JJ8.JPG

http://home.comcast.net/~leadfootdriver/JJ9.JPG

http://home.comcast.net/~leadfootdriver/JJ10.JPG

http://home.comcast.net/~leadfootdriver/JJ11.JPG

http://home.comcast.net/~leadfootdriver/JJ12.JPG

http://home.comcast.net/~leadfootdriver/JJ13.JPG

http://home.comcast.net/~leadfootdriver/JJ14.JPG

[Alexo]

Very interesting... what make and model?

[Reeltarded]

There are like 30 jigs and other devices for alignment, and all of the processes that would make you pull your hair out. lol

Thank God for stores that sell tubes, and the machines that make them.

[katopan]

Great photos. Thanks for posting! I'm also interested in which valve this was?