You also can consider to use ac (directly from your hv-source) for neon lights and triac optocouplers to drive them. eric
_____ From: [email protected] [mailto:[email protected]] On Behalf Of Mike Mitchell Sent: zondag 14 december 2014 17:38 To: [email protected] Subject: [neonixie-l] Re: Polarity and current limiting resistor for INS-1 Nixie Lamps On Saturday, September 29, 2012 6:20:38 PM UTC-4, pwalnuts wrote: Hi! I've been using INS-1 nixie lamps for a while and they have always ended up flickering after a while. I think i might be doing a couple of things wrong. A) Polarity. They light up any which way you wire them. from the Datasheet (link) <http://tubehobby.com/datasheets/ins1.pdf> i can't definitively tell what is the anode and what is the cathode. I know the dot means something, but what it does I don't know. (Picture of INS-1 <http://f.cl.ly/items/2g0Z301L1c3f2y1R0n1e/Image%202012-09-29%20at%204.51.03 %20PM.png> ) I have tried wiring them either way and they still flicker... This is what I think it should be http://f.cl.ly/items/ <http://f.cl.ly/items/2u1p3x3V263X3e3M0s3o/Image%202012-09-29%20at%205.34.01 %20PM.png> 2u1p3x3V263X3e3M0s3o/Image%202012-09-29%20at%205.34.01%20PM.png, is this correct? B) Current. I have a 170 VDC power supply with a 221k Ohm current limiting resistor. It has been been running at 0.55mA. I'm now trying a higher current limiting resistor that brings the current down to 0.45mA. Seems to be working, but I've had ones that worked before and then they start flickering. Thanks for any help! There have been several topics in this group discussing the "wobble" problem with INS-1 neon lamps. I've run into this problem myself using the INS-1 lamps as colon indicators for clocks. One clock's colons are fine after six months, another has only one lamp working after 4 months. Like you, I assumed that the dot/arrow indicate the cathode (negative) terminal. Several other posts say that the dot/arrow indicate the anode (positive) terminal, like https://groups.google.com/forum/?utm_source=digest&utm_medium=email/#!search in/neonixie-l/INS-1/neonixie-l/KZccbl9bFIg/zffZFEdK1PQJ or https://groups.google.com/forum/?utm_source=digest&utm_medium=email/#!search in/neonixie-l/INS-1/neonixie-l/awtYADE5WKo/b42oQ_JhfYIJ I recently received a bag of 100 of the INS-1 lamps so I decided to experiment. I rigged up a breadboard with a full-wave rectifier, 68uf of filtering and a bank of 220K current-limiting resistors. I connected the dot/arrow leg of the lamp to the negative supply, and the other leg through the current limiting resistor to the positive supply. After several hours I would check for flickering/wobble. If a lamp was flickering, I would reverse it's polarity so the dot/arrow leg was positive. If the lamp still flicker after that I would remove it, move the lamps below it up one position on the bread board, and place a fresh lamp in the last position (dot/arrow to negative). After performing this test I found twelve of the one hundred lamps did not flicker, and every one of them were connected with the dot/arrow to the positive supply. On some of the flickering lamps I tried a 180k resistor instead of 220k, connecting positive to the dot/arrow. The higher current through the lamp made no difference, the lamp still flickered. -- 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/b5ae5ec9-f793-4fd1-8597-833c5c4 d70d0%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/b5ae5ec9-f793-4fd1-8597-833c5c 4d70d0%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!AAAAAAAAAAAYAAAAAAAAAPDddShx705MuX20yCpp0vvCgAAAEAAAAHXqsaJiw9NPtAMJUuiF%2BPQBAAAAAA%3D%3D%40zeelandnet.nl. For more options, visit https://groups.google.com/d/optout.
