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Gas bulbs - avalanche effect

  1. Apr 7, 2010 #1
    Hi,

    Any recommendations on gas bulbs with breakdown voltages less than 150 volts. Most importantly it must have high off resistance, at least 20 Gohm.

    I've tested a few fluorescent starters. The best one so far was an old starter with 6 Gohm resistance up to its breakdown voltage of 107 volts. These starter bulbs usually have neon gas. Maybe there are bulbs with different gas that has higher off resistance at comparable breakdown voltages?

    Thanks for any help. It's greatly appreciated!
    Paul Lowrance
     
  2. jcsd
  3. Apr 7, 2010 #2
    Last edited by a moderator: Apr 25, 2017
  4. Apr 7, 2010 #3
    Hi,

    It was my mistake. It should be 20 *tera* ohms minimum, not 20 mega ohms. Maybe another type of gas might have that much resistance?

    Regards,
    Paul
     
  5. Apr 7, 2010 #4
    I knew of someone who used ultra clean NE-2 bulbs with pigtail leads in a negative resistance oscillator circuit to measure picoamp currents by putting a very small capacitor (50 pF?) in parallel and counting the time between avalanche pulses, but the last time I saw him he was unable to get NE-2's that had sufficiently low leakage. Get some and maybe you can make them work. See IPDIC chamber circuit here:

    http://www.orau.org/PTP/collection/surveymeters/ipdic.htm

    Bob S.
     
    Last edited: Apr 7, 2010
  6. Apr 8, 2010 #5
    BTW, this topic is regarding my research. Please see the thread titled, "Excess energy detected from piezos & diodes"

    A few minutes ago I just changed my account settings to give people access to my email address.

    Regards,
    Paul Lowrance
     
  7. Apr 8, 2010 #6

    berkeman

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    Staff: Mentor

    That thread was closed and deleted because it did not meet the PF Rules. Do not try to re-open a closed topic. You need to post within the PF Rules, or you will not be allowed to post here.
     
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