Rerurn to Romy the Cat's Site

Hi Romy,

Still playing with Gas zeners, isn't it ?

I once seen, tested and scrapped "dead" ones....
Clue#1: they fire and (try to) regulate at higher than nominal voltages at normal current and are erratic.
Clue#2: they have sections (at top and bottom, usually, where is the gap between the outer shell and the mica spacer) of the internal glass internally "plated" by the anode metal ions that have drifted reverse to the electron flow inside. BTW, the center rod is the Anode (positive) the external "plate" is really the cathode (negative): the reverse of a "normal" heated-cathode tube. That "ionic" plating looks like the top getter, but is more aluminum like in colour.

Such condition, I guess, cannot be acquired otherwise than by operating few THOUSANDS hours, maybe in excess of 10,000 ? I don't know... I never had enough patience to test that.

The ones I tested a long time ago (military surplus, again) that behaved like that are now lying in some burial site, I guess.

May they Rest In Pieces.....

Best regards,

Rerurn to Romy the Cat's Site