On Fri 2019-01-04T17:05:21-0500 paul swed hath writ: > Ed agree with your coment that a 30 or greater year old led may be dimming.
Not nearly as much as an entirely different clock illumination: radium watch dial paint I remember my mom's wind-up travel clock glowing brightly. 50 years later there is nothing. I brought it into the lab just to check that it is still radioactive (wouldn't want to have lost that radium somewhere). It's the zinc sulfide crystals, the radiation damages them and they stop producing light. -- Steve Allen <[email protected]> WGS-84 (GPS) UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
