There is an other source of UV-LED's. Not as cheap as on eBay, but they can serve shorter wavelengths (until 245nm as I remember). [ http://www.roithner-laser.com/ ] They will ship also small quantities. 400nmis actually no UV, but violet. 380 -37 nm should be les visible, because of the peak wavelength is really UV. eric
_____ From: [email protected] [mailto:[email protected]] On Behalf Of petehand Sent: dinsdag 1 april 2014 20:22 To: [email protected] Cc: [email protected] Subject: Re: [neonixie-l] Re: Trigger clock revisited My tubes also came from the "guy in Southampton", though I've forgotten his name. My UV LEDs, on the other hand, came from Best Buy in Hong Kong, via Ebay, for $28 a hundred, and I have no part number or other documentation. Today a quick search for "UV LED" on Ebay returns this as the first result - http://www.ebay.com/itm/NEW-100PCS-5mm-Megabright-Ultra-Violet-LED-UV-Lamp-2 -500mcd-BESTBUY-/290726116420?pt=LH_DefaultDomain_0 <http://www.ebay.com/itm/NEW-100PCS-5mm-Megabright-Ultra-Violet-LED-UV-Lamp- 2-500mcd-BESTBUY-/290726116420?pt=LH_DefaultDomain_0&hash=item43b0a07c44> &hash=item43b0a07c44 Unbelievably they are now only $6 a hundred, with shipping included, which means after taking off the cost of shipping they're more like 2 cents each. You might suspect for that price they're factory rejects, and you might be right, since about one in 4 of my lot was either dead out of the bag or failed after a minute's use, but who the heck cares when they're cheaper than their own series resistor. On Tuesday, April 1, 2014 7:02:12 AM UTC-7, Nick wrote: For the last Lord knows how many years I've been intending to follow in Grahame's footsteps and build an XC-18 clock - I picked up 300 of these many years back when the guy in Southampton only wanted about 10p each for them - hopefully enough for two clocks. I'm impressed with Pete's results - it's good that the theory is being tested and the results quantified as the "triggering in the dark" issue has been around for a while - Kr85, as has been pointed out, was used for specifically this reason, but is no longer viable. Let's hope that Pete's experiments results are repeatable - do you have the details of the emission characteristics of those LEDs? Cheers Nick -- 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 [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/55bd08fc-7e45-43bc-a928-bdc8bc5 644de%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/55bd08fc-7e45-43bc-a928-bdc8bc 5644de%40googlegroups.com?utm_medium=email&utm_source=footer> . For more options, visit https://groups.google.com/d/optout. -- 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 [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/!%26!AAAAAAAAAAAYAAAAAAAAAPDddShx705MuX20yCpp0vvCgAAAEAAAAP49yJaWanFDpTolrtrt9W0BAAAAAA%3D%3D%40zeelandnet.nl. For more options, visit https://groups.google.com/d/optout.
