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Re: Exhausted

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On Wednesday, March 16, 2016 at 1:32:54 PM UTC-4, John Larkin wrote:
> On Wed, 16 Mar 2016 08:04:34 -0700 (PDT), George Herold
> <gherold@teachspin.com> wrote:
> 
> >On Wednesday, March 16, 2016 at 10:33:03 AM UTC-4, Winfield Hill wrote:
> >> George Herold wrote...
> >> >
> >> >On Wednesday, March 16, 2016 at 1:53:11 AM UTC-4, David Eather wrote:
> >> >> If any kind soul can help...
> >> >> 
> >> >> There was a short post/note on SED or SEB about a transistor with a 2.5V  
> >> >> max Vebo and another one with 3.0 max Vebo. I have spent hours looking for  
> >> >> the transistors and have run out of options. Does anyone remember which  
> >> >> transistor numbers these were?
> >> >> 
> >> >> I'm adding transistor junction breakdown noise to a Arduino and they would  
> >> >> fit the bill perfectly - and cut out problem of providing extra voltage  
> >> >> sources other than %v power from USB.
> >> >> 
> >> >> As always TIA.
> >> > 
> >> > I don't know the transistors, but have you tried a low voltage zener.  
> >> > (The problem with both is that you may not get much more than just the 
> >> > shot noise.)  
> >> 
> >>  Agreed, the zener noise mechanism comes from avalanche, which
> >>  doesn't kick in until you get to voltages above about 8 volts.
> >>  Low-current "microplasmas" form and quickly terminate after
> >>  discharging the zener's self capacitance, creating a kind of
> >>  popcorn noise.   There are extensive threads on the subject
> >>  15-20 years ago on s.e.d., where I spent a month (haha, more)
> >>  making and posting all kinds of nanosecond-scale measurements.
> >> 
> >>  The zener physics effect (field emission) predominates at
> >>  low-voltages, see the ON Semi handbook, HBD854, page 20. 
> >>  https://www.onsemi.com/pub/Collateral/HBD854-D.PDF
> >> 
> >> 
> >> -- 
> >>  Thanks,
> >>     - Win
> >
> >Grin.. everyone should spend a month playing with avalanche breakdown.  
> >
> >Say Win, If you want to "waste" a few more hours with avalanches, 
> >I can send you some LED's that breakdown ~25 Volts and are 
> >single photon detectors. (Spad's)  They make great little experiments 
> >for electronics courses.  (perhaps Paul would be more interested?)  
> >These.. you can also get them from Newark.
> >http://www.purdyelectronics.com/pdf/AND113R.pdf
> >
> >A newsletter.
> >http://nebula.wsimg.com/0b846f1e91ab9c7442a61c8c35680a51?AccessKeyId=027C3581808C75E81679&disposition=0&alloworigin=1
> >
> >George H. 
> >   
> 
> They would make a pretty good noise seed, probably even in the dark.

Well maybe, probably not in the dark.  About 10-20% of them show  a lot 
of after pulsing... breaking down almost all the time even in the dark.
 (After the channel breaks down, there are dangling 
charges left around and those can cause it to break down again.)  
So there is not a random distribution of pulses, but a large chance of 
having another pulse soon after one has happened.   That shows up in the 
statistics.. you get a kinda 1/f distribution of times and not the expected 
exponential.  

George H. 
> 
> 
> -- 
> 
> John Larkin         Highland Technology, Inc
> picosecond timing   precision measurement 
> 
> jlarkin att highlandtechnology dott com
> http://www.highlandtechnology.com

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Exhausted  "David Eather" <eather@tpg.com.au> - 2016-03-16 15:53 +1000
  Re: Exhausted Klaus Kragelund <klauskvik@hotmail.com> - 2016-03-16 01:07 -0700
  Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-16 06:04 -0700
    Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-17 00:16 +1000
      Re: Exhausted Allan Herriman <allanherriman@hotmail.com> - 2016-03-16 16:35 +0000
        Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-16 11:15 -0700
          Re: Exhausted Allan Herriman <allanherriman@hotmail.com> - 2016-03-17 12:11 +0000
      Re: Exhausted mrdarrett@gmail.com - 2016-03-17 10:37 -0700
        Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 07:25 +1000
          Re: Exhausted mrdarrett@gmail.com - 2016-03-17 15:05 -0700
    Re: Exhausted Winfield Hill <hill@rowland.harvard.edu> - 2016-03-16 07:32 -0700
      Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-16 08:04 -0700
        Re: Exhausted Winfield Hill <hill@rowland.harvard.edu> - 2016-03-16 08:16 -0700
        Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 10:32 -0700
          Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-16 11:08 -0700
            Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 12:30 -0700
              Re: Exhausted Clifford Heath <no.spam@please.net> - 2016-03-17 06:47 +1100
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 17:01 -0700
                Re: Exhausted Clifford Heath <no.spam@please.net> - 2016-03-17 07:01 +1100
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 17:27 -0700
                Re: Exhausted Piotr Wyderski <peter.pan@neverland.mil> - 2016-03-17 17:35 +0100
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-17 10:13 -0700
                Re: Exhausted Clifford Heath <no.spam@please.net> - 2016-03-18 11:38 +1100
                Re: Exhausted dplatt@coop.radagast.org (Dave Platt) - 2016-03-16 17:17 -0700
                Re: Exhausted Lasse Langwadt Christensen <langwadt@fonz.dk> - 2016-03-16 17:21 -0700
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 17:39 -0700
                Re: Exhausted "Tim Williams" <tiwill@seventransistorlabs.com> - 2016-03-16 21:24 -0500
                Re: Exhausted Phil Hobbs <pcdhobbs@gmail.com> - 2016-03-16 20:51 -0700
                Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-16 20:21 -0700
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 21:16 -0700
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 17:34 -0700
                Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 07:31 +1000
                Re: Exhausted rickman <gnuarm@gmail.com> - 2016-03-17 00:01 -0400
                Re: Exhausted Clifford Heath <no.spam@please.net> - 2016-03-17 14:09 +1100
                Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-17 09:01 -0700
                Re: Exhausted Piotr Wyderski <peter.pan@neverland.mil> - 2016-03-17 17:46 +0100
                Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 07:33 +1000
                Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 07:35 +1000
                Re: Exhausted Piotr Wyderski <peter.pan@neverland.mil> - 2016-03-18 11:44 +0100
      low-voltage low-current noise sources Winfield Hill <hill@rowland.harvard.edu> - 2016-03-16 08:10 -0700
  Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-16 08:35 -0700
    Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 07:52 +1000
      Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-17 15:35 -0700
        Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 09:09 +1000
          Re: Exhausted John Larkin <jjlarkin@highlandtechnology.com> - 2016-03-17 16:54 -0700
          Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-17 17:40 -0700
            Re: Exhausted mixed nuts <melopsitticus@undulatus.budgie> - 2016-03-17 22:37 -0400
        Re: Exhausted "David Eather" <eather@tpg.com.au> - 2016-03-18 09:09 +1000
        Re: Exhausted George Herold <gherold@teachspin.com> - 2016-03-17 17:29 -0700

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