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Re: Exhausted

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On Fri, 18 Mar 2016 03:37:21 +1000, <mrdarrett@gmail.com> wrote:

> On Wednesday, March 16, 2016 at 7:16:26 AM UTC-7, David Eather wrote:
>> On Wed, 16 Mar 2016 23:04:13 +1000, George Herold  
>> <gherold@teachspin.com>
>> 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.)
>> >
>> > George H.
>>
>> Zener is OK but my experiments suggest noise is about an order of
>> magnitude lower. On the plus side transistor junctions seem to 'age' and
>> become quieter as time goes on. (both effects may be non-existent and  
>> just
>> the result of my poor experiments)
>
>
> (Beginner here)
>
> Say, did you mean that transistors get quieter as they age?
>
> (intrigued)
>
> Michael

When you reverse bias the emitter to base junction enough it breaks down  
and produces lots of random electrical noise, but over time the amount of  
noise decreases and after a long time (many months or years) it may no  
longer produce enough noise to be useful. It also ruins the transistor for  
anything else.

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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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