Ben - You can just reduce the resistor value slightly to increase the current. At 180V, you had 2mA with a 32K resistor; using ohms law, the voltage-drop across the resistor is 32K * 2mA = 64V. Since the power supply is 180V, the voltage across the nixie tube is about 116V.
To calculate the value for 2.9mA, assume the voltage on the nixie tube is still 116V. In reality it will be a bit higher due to more current, but for simplicity assume its the same. So, the new resistor value is 64V/2.9mA = 22K (a common value). On Friday, April 21, 2023 at 1:23:24 PM UTC-7 Adrian Godwin wrote: > When I wanted a higher voltage supply to refresh some tubes, I found an > electrophoresis supply on ebay (Shandon Vokam 400-100). It provides up to > 400V at 100mA with voltage/current metering and did a good job for me. I > think it cost me about £40. > > > On Fri, Apr 21, 2023 at 9:19 PM Benoit Tourret <[email protected]> > wrote: > >> I don't know how to rise the intensity... >> I wish I had a laboratory DC power supply, but mine stops at 30V. >> so I put a NCH6300HV to raise the voltage. If I can adjust the voltage, >> I cannot adjust anything else. >> however I added a voltmeter and ammeter to check what I'm sending to the >> tube. Do you know if there is an adjustable power supply that can be used >> for our beloved tubes? >> So, I regulate the voltage and I check that I do not exceed the desired >> values. >> >> should I change the 32K resistor between the PS and the tube? could a >> potentiometer be used? >> >> So I did see an improvement. but some need to be "heated". I of course >> doesn't speak of temperature, but they need 10 to 20 seconds to get their >> full glow, a bit like a neon tube with an old starter. >> They are 52 years old now and never been used. >> >> Le vendredi 21 avril 2023 à 16:20:59 UTC+2, gregebert a écrit : >> >>> The IN-1 datasheet says 2.5mA typical operating current, so you should >>> try cleaning the other 3 tubes at just under 3mA. The other 7 tubes might >>> clean-up on their own at normal current if the usage is balanced. >>> >>> So did you see some improvement ? >>> >>> On Friday, April 21, 2023 at 12:14:05 AM UTC-7 Benoit Tourret wrote: >>> >>>> I ran each tube with 180V 2mA / two hours, turning each plate for 2 >>>> minutes. >>>> >>>> on 10 tubes: >>>> >>>> 7 are OK >>>> 3 are not perfect. >>>> >>>> I will wait to be able to lit them all together. >>>> >>>> >>>> Le jeudi 20 avril 2023 à 01:27:40 UTC+2, gregebert a écrit : >>>> >>>>> I couldn't resist asking google Bard this question: Are IN-1 nixie >>>>> tubes reliable ? >>>>> Well, here's the answer. Feel free to laugh.....love the part about >>>>> the filaments. Geez, maybe that's why I had so much trouble with mine ? >>>>> >>>>> IN-1 nixie tubes are generally reliable, but they can fail over time. >>>>> The most common failure mode is a leak in the vacuum tube. This can >>>>> happen >>>>> due to a number of factors, including manufacturing defects, physical >>>>> damage, or exposure to extreme temperatures. >>>>> >>>>> If a leak develops, the tube will slowly fill with air and the >>>>> filaments will eventually burn out. This can happen over a period of >>>>> months >>>>> or even years. To prevent leaks, it is important to store IN-1 nixie >>>>> tubes >>>>> in a cool, dry place and to avoid dropping or banging them. >>>>> >>>>> Another potential failure mode is a failure of the heater filament. >>>>> This can happen due to a number of factors, including overheating, >>>>> overvoltage, or physical damage. If the heater filament fails, the tube >>>>> will not light up. >>>>> >>>>> To prevent heater filament failures, it is important to use a >>>>> regulated power supply and to avoid exceeding the maximum operating >>>>> voltage. >>>>> >>>>> On Tuesday, April 18, 2023 at 2:03:54 PM UTC-7 gregebert wrote: >>>>> >>>>>> I never had an IN-1 run long enough to get poisoned. Mine developed >>>>>> internal shorts, resulting in 2 numerals glowing at the same time. >>>>>> From what I've heard, nixie degradation increases exponentially with >>>>>> current, so you want to stay as close as possible to normal operating >>>>>> current. Try running the worst digit continuously for a few hours at 20% >>>>>> higher current, and see if that helps. I was (briefly) drawn to the IN-1 >>>>>> over 10 years ago because of the large size for the low cost; I bought a >>>>>> case of 25 for around 40USD including shipping. Only a few survive today >>>>>> that weren't dissected or tortured in a microwave oven (yeah, pretty >>>>>> hilarious but kinda toxic because of the bakelite). >>>>>> >>>>>> A few of the IN-18's in my clock have shown signs of poisoning even >>>>>> though I run a cleansing routine for 1 hour every night. This is >>>>>> most-visible on the first day of the month for the months digit, and it >>>>>> can >>>>>> take a few days to recover. This clock has 14 tubes; kinda ridiculous >>>>>> but >>>>>> it looks impressive. It was inspired by the movie "Tomorrowland", which >>>>>> has >>>>>> a brief scene with two 6-digit IN-18 clocks. I'm certain one of our >>>>>> neonixie members is the creator of that clock (that was an invitation >>>>>> for >>>>>> you to take a well-deserved bow...). >>>>>> >>>>>> Tubes that run 0-9 during the day need no cleansing (unit seconds, >>>>>> unit minutes, unit hours). Tubes the run 0-5 during the day are cleansed >>>>>> by >>>>>> running 6-9 (tens seconds, tens minutes). Tubes that are static, or near >>>>>> static (tens hours, month, day, year) run 0-9 for cleansing. >>>>>> >>>>>> The static tubes, notably the 4-digit year, show very little signs of >>>>>> poisoning because I have swapped them around to put the >>>>>> most-vulnerable-to-poisoning tubes where they run 0-9 during the day. >>>>>> >>>>>> I havn't seen any signs of poisoning on Burroughs tubes. >>>>>> >>>>>> On Tuesday, April 18, 2023 at 11:39:54 AM UTC-7 Benoit Tourret wrote: >>>>>> >>>>>>> Hello, I have some IN-1 that seems to be poisoned. poisoned or >>>>>>> rather oxided, as they seems to be really new. it is fine mesh from >>>>>>> September 1971. >>>>>>> two of them are fine after one or two day, tree other doesn't show >>>>>>> any improvement. >>>>>>> >>>>>>> I read that I must overload them a while but how many and how long >>>>>>> should I keep one digit on before light the next digit ? is it 1 second >>>>>>> or >>>>>>> one day... >>>>>>> >>>>>>> by the way, as I read that this tube doesn't have mercury inside, >>>>>>> can it be unpoisonned ? >>>>>>> >>>>>> -- >> > 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 view this discussion on the web, visit >> https://groups.google.com/d/msgid/neonixie-l/b554ff13-3806-4c16-af85-8bb7bb10e277n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/neonixie-l/b554ff13-3806-4c16-af85-8bb7bb10e277n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. 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