Those UV LEDs generate a LOT of UV. I use one as a color tester for my neon shop (most colors of neon tubing look white when off). Glad you didn't hurt your eyes. Problem is, the glass is opaque to UV.
If you don't mind spending the money you can reactivate the tubes. One can buy a microcurie of Cs-137 without a license. It can be had epoxied to the head of a pin. 1uCi is more than enough to strike a couple of tubes. Position the source in an inconspicuous place between two tubes and it'll work for both of them. Cs-137 emits a good healthy 661keV gamma ray that will easily penetrate the glass and cause bunches of secondary electrons. I just tried this using a 30 year old source (down to half a uCi) on a flickering neon bulb on some old test equipment. I just held the source against the plastic lens and the lamp glow went steady. The only downside is that a pin source will run you about $60. If anyone is interested in this route, I'll dig up some names of some suppliers. John On 02/10/2014 05:10 AM, Nick wrote: > Some time ago I was playing with XC18s (bought a large number many years > ago when they were very cheap) - they have a similar problem so I > experimented with uranium marbles and UV LEDs... > > I wasn't very "quantitative", but from a qualitative standpoint, the > marbles made no difference and at that time so-called "UV" LEDs didn't seem > to have much UV content - more just purple... > > Maybe things have improved since then and UV LEDs are a possible answer. > All you need is a good source of high energy photons to initiate > ionisation... > > Nick > -- John DeArmond Tellico Plains, Occupied TN http://www.fluxeon.com <-- THE source for induction heaters http://www.neon-john.com <-- email from here http://www.johndearmond.com <-- Best damned Blog on the net PGP key: wwwkeys.pgp.net: BCB68D77 -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/52F8BBE7.8040805%40neon-john.com. For more options, visit https://groups.google.com/groups/opt_out.