Did you already try to diminish the current through the LED's to lower the trigger sensitivity? An other idea to pack the trigger tubes in sleeves of tubing to separate them from each others. Don't forget also the gas in the tubes has some spectral emission in the UV region that influences the neighboring tubes' trigger level. eric
_____ From: [email protected] [mailto:[email protected]] On Behalf Of petehand Sent: zaterdag 29 maart 2014 8:59 To: [email protected] Subject: [neonixie-l] Trigger clock revisited <https://lh4.googleusercontent.com/-CVvQ07rOmw0/UzZ7zBoB0WI/AAAAAAAAAHc/Yz_B HkKvUmI/s1600/trig1.jpg> A few years ago - well, maybe seven - I made a trigger clock inspired by the one on Grahame Marsh's web site. I could never get the darn thing to work reliably in the dark - some rings would get stuck at random intervals - so I shelved it. I dug it out recently because I needed to use its HV power supply to un-poison some nixies, and decided to have another go at it. I put rows of UV LEDs down alongside the rings. Now it has the opposite problem! The UV light made the tubes so sensitive that some would trigger just with the touch of a finger. I had to put black card barriers between the columns to stop the light getting to the nixie driver columns, because they were flickering on and off at random, and slide black sleeving over a few counting tubes. It's not that they wouldn't go out, but that they'd trigger on when it was a different tube's turn. I still haven't got all the bugs out - it seems to gain about 12 hours a day, and not in whole hour increments. I THINK this is because the 50 minute trigger tube sometimes fires on the wrong pulse and cuts the hour short. I did once see this - it counted 57, 58, 58, 00 (the glow transferred to 00) and then back to 51, 52 etc, but I haven't been able to catch it doing so again. Anyway, I just wanted to share that UV (Ultra Viagra?) really does make these old tubes frisky again. Sorry about the terrible picture, I shot it in low light, my camera seems to be rather sensitive to UV, and the clock is behind glass to keep the dust off. It looks in the pic as if the LEDs are really glaring bright, and you can see the UV glow spread out in front of them. In fact to the naked eye, you can barely see any light at all, it's just a hint you see out of the corner of your eye. The LEDs are running at only 1 milliamp. -- 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/420542f9-24ad-4258-9473-5cfc6d1 0be6a%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/420542f9-24ad-4258-9473-5cfc6d 10be6a%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!AAAAAAAAAAAYAAAAAAAAAPDddShx705MuX20yCpp0vvCgAAAEAAAADAvIhHbSjZPkrXpLrxkKXABAAAAAA%3D%3D%40zeelandnet.nl. For more options, visit https://groups.google.com/d/optout.
