My obscure interest: Vacuum Fluorescent Displays

[mbates14]

yes they do. it works EXACTLY like a CRT. if you look on the filaments of a nice fresh VFD, it has a "white" coating, thats the cathode coating that emits the electrons. the barium or whatever it is.

as the VFD wears, it turns darker and darker. When the VFD goes completely dim or dead, youll see the barium coated filament cathodes have almost no white left.

[Ed in Tx]

Originally Posted by mbates14

..as the VFD wears, it turns darker and darker. When the VFD goes completely dim or dead, youll see the barium coated filament cathodes have almost no white left.

What's amazing is I have pioneer DT-400 digital timer with a VFD, been plugged in continuously for 32 years, that's over 280,300 hours! Still as bright as it was new best as I can tell. Lights up the kitchen at night, where it's served as a coffee pot timer since new in 1979.

[OvenMaster]

Originally Posted by mbates14

yes they do. it works EXACTLY like a CRT. if you look on the filaments of a nice fresh VFD, it has a "white" coating, thats the cathode coating that emits the electrons. the barium or whatever it is.

as the VFD wears, it turns darker and darker. When the VFD goes completely dim or dead, youll see the barium coated filament cathodes have almost no white left.

So this explains why the VFD clock display on my Amana electric range is slowly dimming after 12 years of 24/7 use. It's also brighter at the ends of each segment, darker in the middles. Normal, yes?

One question: what are the incredibly thin glowing red lines that you see going across the face of the VFD? My range clock, my Casio calculator, my old Technics SA-222, my Marantz CD player, my Sony cassette deck, and my Panasonic VCR has them...

[RobNor]

Has VFD,nixie tubes and a beam deflection decade counter clock

http://www.tube-tester.com/sites/nixie/nixie-tubes.htm