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Groups > sci.electronics.design > #461110 > unrolled thread
| Started by | Chris <cbx@noreply.com> |
|---|---|
| First post | 2017-05-21 11:06 +0000 |
| Last post | 2017-06-06 18:29 -0700 |
| Articles | 20 on this page of 45 — 20 participants |
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Combating Zener Jitter Chris <cbx@noreply.com> - 2017-05-21 11:06 +0000
Combating Zener Jitter pcdhobbs@gmail.com - 2017-05-21 04:27 -0700
Re: Combating Zener Jitter Rafael Deliano <rafael_deliano@arcor.de> - 2017-05-21 16:30 +0200
Re: Combating Zener Jitter Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2017-05-21 17:51 +0200
Re: Combating Zener Jitter Cursitor Doom <curd@notformail.com> - 2017-05-21 15:55 +0000
Re: Combating Zener Jitter Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-21 09:03 -0700
Re: Combating Zener Jitter Cursitor Doom <curd@notformail.com> - 2017-05-21 16:29 +0000
Re: Combating Zener Jitter Winfield Hill <hill@rowland.harvard.edu> - 2017-05-21 17:10 -0700
Re: Combating Zener Jitter Cursitor Doom <curd@notformail.com> - 2017-05-22 14:01 +0000
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-22 07:33 -0700
Re: Combating Zener Jitter Jon Elson <elson@pico-systems.com> - 2017-05-22 12:02 -0500
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-22 11:29 -0700
Re: Combating Zener Jitter Jon Elson <jmelson@wustl.edu> - 2017-05-22 13:48 -0500
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-22 13:28 -0700
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-23 06:28 -0700
Re: Combating Zener Jitter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-23 10:38 -0400
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-23 08:11 -0700
Re: Combating Zener Jitter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-23 11:36 -0400
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-23 09:28 -0700
Re: Combating Zener Jitter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-22 15:12 -0400
Re: Combating Zener Jitter John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-22 12:48 -0700
Re: Combating Zener Jitter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-22 15:57 -0400
Re: Combating Zener Jitter John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-22 21:07 -0700
Re: Combating Zener Jitter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-23 10:40 -0400
Re: Combating Zener Jitter John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-23 09:06 -0700
Re: Combating Zener Jitter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-23 12:12 -0400
Re: Combating Zener Jitter Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-23 17:46 +0000
Re: Combating Zener Jitter John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-23 11:18 -0700
Re: Combating Zener Jitter Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-23 19:35 +0000
Re: Combating Zener Jitter John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-23 21:18 -0700
Re: Combating Zener Jitter Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-24 16:35 +0000
Re: Combating Zener Jitter John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-25 08:12 -0700
Re: Combating Zener Jitter Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-25 15:24 +0000
Re: Combating Zener Jitter Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-25 07:40 +0000
Re: Combating Zener Jitter Clifford Heath <no.spam@please.net> - 2017-05-25 17:44 +1000
Re: Combating Zener Jitter Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-25 07:52 +0000
Re: Combating Zener Jitter George Herold <gherold@teachspin.com> - 2017-05-22 13:33 -0700
Re: Combating Zener Jitter "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> - 2017-05-27 15:53 -0400
Re: Combating Zener Jitter Winfield Hill <hill@rowland.harvard.edu> - 2017-05-27 19:15 -0700
Re: Combating Zener Jitter "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-05-21 11:29 -0500
Re: Combating Zener Jitter krw@notreal.com - 2017-05-21 16:59 -0400
Re: Combating Zener Jitter Jon Elson <elson@pico-systems.com> - 2017-05-21 12:07 -0500
Combating Zener Jitter Anthony Stewart <tony.sunnysky@gmail.com> - 2017-05-29 10:42 -0700
Re: Combating Zener Jitter Robert Baer <robertbaer@localnet.com> - 2017-05-30 01:14 -0800
Re: Combating Zener Jitter Anthony Stewart <tony.sunnysky@gmail.com> - 2017-06-06 18:29 -0700
Page 2 of 3 — ← Prev page 1 [2] 3 Next page →
| From | John Larkin <jjlarkin@highland_snip_technology.com> |
|---|---|
| Date | 2017-05-22 12:48 -0700 |
| Message-ID | <c2g6ic1q1u9sda3p4ob1pq76n5ls37ivdu@4ax.com> |
| In reply to | #461285 |
On Mon, 22 May 2017 15:12:20 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >On 05/22/2017 10:33 AM, George Herold wrote: >> On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: >>> Cursitor Doom wrote... >>>> >>>> Jim Thompson wrote: >>>> >>>>> AKA Flicker Noise >>>> >>>> Yup, pink noise. No jittering/jitterbugging involved. ;) >>> >>> Actually, I'd say you're wrong. The zener noise that we >>> see in avalanche mode (greater then 7 volts or so) is due >>> to step-wise "microplasma" ns-scale changes in current. >>> A decade or so ago we fully discussed it here on s.e.d., >>> complete with measurements, waveforms, detailed physics >>> paper references and the works. Nailed it down. As it >>> happens, the jitterbug analogy isn't so far off. >> >> Those are some nice threads, I went back and read them a few years >> ago. Turning lemons into lemonade, a 20V zener baised at ~10uA >> makes a nice noise source out to ~100's of kHz. >> >> I've also been reading Hamamatsu app notes on their Silicon PMT. >> Which is really a Si avalanche photodiode in "Geiger-mode" >> (biased above the breakdown voltage.) Fun stuff. >> >> George H. > >I'm in conversation with a big biosci company about cost-reducing their >detection subsystems, so this has come up a lot lately. "Si PMTs" are >basically an array of APDs wired in parallel and run in Geiger mode. >The idea is that having multiple pixels allows you to extend Geiger mode >to pulses containing more photons without losing resolution. > >AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when >uniformly illuminated they start to become nonlinear at depressingly low >photon numbers--the linearity error is 10% once 10% of the pixels have >fired, because only 90% are available. > >You can apply a correction for this that might work adequately up to >about 25%, but it starts to run out of gas pretty fast compared with a >real PMT. Their dynamic range requirements were much too large for this >to work for them. > >Also the dark counts are ridiculously worse--more than 10**6 times worse >on an area basis. > >The real advantage of MPPCs is that you can do thresholding, which helps >reject single-pixel events at the expense of sensitivity. That reduces >the effective dark count rate by a lot. > >Cheers > >Phil Hobbs If your customer is gigantic enough, maybe Hamamatsu would sell them the cute little MEMS PMTs. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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| From | Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> |
|---|---|
| Date | 2017-05-22 15:57 -0400 |
| Message-ID | <U8KdnYa2HskE377EnZ2dnUU7-f2dnZ2d@supernews.com> |
| In reply to | #461288 |
On 05/22/2017 03:48 PM, John Larkin wrote: > On Mon, 22 May 2017 15:12:20 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 05/22/2017 10:33 AM, George Herold wrote: >>> On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: >>>> Cursitor Doom wrote... >>>>> >>>>> Jim Thompson wrote: >>>>> >>>>>> AKA Flicker Noise >>>>> >>>>> Yup, pink noise. No jittering/jitterbugging involved. ;) >>>> >>>> Actually, I'd say you're wrong. The zener noise that we >>>> see in avalanche mode (greater then 7 volts or so) is due >>>> to step-wise "microplasma" ns-scale changes in current. >>>> A decade or so ago we fully discussed it here on s.e.d., >>>> complete with measurements, waveforms, detailed physics >>>> paper references and the works. Nailed it down. As it >>>> happens, the jitterbug analogy isn't so far off. >>> >>> Those are some nice threads, I went back and read them a few years >>> ago. Turning lemons into lemonade, a 20V zener baised at ~10uA >>> makes a nice noise source out to ~100's of kHz. >>> >>> I've also been reading Hamamatsu app notes on their Silicon PMT. >>> Which is really a Si avalanche photodiode in "Geiger-mode" >>> (biased above the breakdown voltage.) Fun stuff. >>> >>> George H. >> >> I'm in conversation with a big biosci company about cost-reducing their >> detection subsystems, so this has come up a lot lately. "Si PMTs" are >> basically an array of APDs wired in parallel and run in Geiger mode. >> The idea is that having multiple pixels allows you to extend Geiger mode >> to pulses containing more photons without losing resolution. >> >> AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when >> uniformly illuminated they start to become nonlinear at depressingly low >> photon numbers--the linearity error is 10% once 10% of the pixels have >> fired, because only 90% are available. >> >> You can apply a correction for this that might work adequately up to >> about 25%, but it starts to run out of gas pretty fast compared with a >> real PMT. Their dynamic range requirements were much too large for this >> to work for them. >> >> Also the dark counts are ridiculously worse--more than 10**6 times worse >> on an area basis. >> >> The real advantage of MPPCs is that you can do thresholding, which helps >> reject single-pixel events at the expense of sensitivity. That reduces >> the effective dark count rate by a lot. >> >> Cheers >> >> Phil Hobbs > > If your customer is gigantic enough, maybe Hamamatsu would sell them > the cute little MEMS PMTs. Wouldn't that be nice! Of course the designer has probably died of old age by now.... Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-05-22 21:07 -0700 |
| Message-ID | <l1d7ich53rvqrc2a4v6sfsst9ama1hkfqk@4ax.com> |
| In reply to | #461291 |
On Mon, 22 May 2017 15:57:13 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >On 05/22/2017 03:48 PM, John Larkin wrote: >> On Mon, 22 May 2017 15:12:20 -0400, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> On 05/22/2017 10:33 AM, George Herold wrote: >>>> On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: >>>>> Cursitor Doom wrote... >>>>>> >>>>>> Jim Thompson wrote: >>>>>> >>>>>>> AKA Flicker Noise >>>>>> >>>>>> Yup, pink noise. No jittering/jitterbugging involved. ;) >>>>> >>>>> Actually, I'd say you're wrong. The zener noise that we >>>>> see in avalanche mode (greater then 7 volts or so) is due >>>>> to step-wise "microplasma" ns-scale changes in current. >>>>> A decade or so ago we fully discussed it here on s.e.d., >>>>> complete with measurements, waveforms, detailed physics >>>>> paper references and the works. Nailed it down. As it >>>>> happens, the jitterbug analogy isn't so far off. >>>> >>>> Those are some nice threads, I went back and read them a few years >>>> ago. Turning lemons into lemonade, a 20V zener baised at ~10uA >>>> makes a nice noise source out to ~100's of kHz. >>>> >>>> I've also been reading Hamamatsu app notes on their Silicon PMT. >>>> Which is really a Si avalanche photodiode in "Geiger-mode" >>>> (biased above the breakdown voltage.) Fun stuff. >>>> >>>> George H. >>> >>> I'm in conversation with a big biosci company about cost-reducing their >>> detection subsystems, so this has come up a lot lately. "Si PMTs" are >>> basically an array of APDs wired in parallel and run in Geiger mode. >>> The idea is that having multiple pixels allows you to extend Geiger mode >>> to pulses containing more photons without losing resolution. >>> >>> AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when >>> uniformly illuminated they start to become nonlinear at depressingly low >>> photon numbers--the linearity error is 10% once 10% of the pixels have >>> fired, because only 90% are available. >>> >>> You can apply a correction for this that might work adequately up to >>> about 25%, but it starts to run out of gas pretty fast compared with a >>> real PMT. Their dynamic range requirements were much too large for this >>> to work for them. >>> >>> Also the dark counts are ridiculously worse--more than 10**6 times worse >>> on an area basis. >>> >>> The real advantage of MPPCs is that you can do thresholding, which helps >>> reject single-pixel events at the expense of sensitivity. That reduces >>> the effective dark count rate by a lot. >>> >>> Cheers >>> >>> Phil Hobbs >> >> If your customer is gigantic enough, maybe Hamamatsu would sell them >> the cute little MEMS PMTs. > >Wouldn't that be nice! Of course the designer has probably died of old >age by now.... > >Cheers > >Phil Hobbs One cool idea is to use a microchannel plate in front of a 2D delay-line detector. That can log the X-Y-T hits of single electrons or photons at a pretty high rate. My only patent is for a delay-line detector, US7019307. -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> |
|---|---|
| Date | 2017-05-23 10:40 -0400 |
| Message-ID | <dKmdnYVJJsxs1LnEnZ2dnUU7-aednZ2d@supernews.com> |
| In reply to | #461316 |
On 05/23/2017 12:07 AM, John Larkin wrote: > On Mon, 22 May 2017 15:57:13 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 05/22/2017 03:48 PM, John Larkin wrote: >>> On Mon, 22 May 2017 15:12:20 -0400, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> On 05/22/2017 10:33 AM, George Herold wrote: >>>>> On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: >>>>>> Cursitor Doom wrote... >>>>>>> >>>>>>> Jim Thompson wrote: >>>>>>> >>>>>>>> AKA Flicker Noise >>>>>>> >>>>>>> Yup, pink noise. No jittering/jitterbugging involved. ;) >>>>>> >>>>>> Actually, I'd say you're wrong. The zener noise that we >>>>>> see in avalanche mode (greater then 7 volts or so) is due >>>>>> to step-wise "microplasma" ns-scale changes in current. >>>>>> A decade or so ago we fully discussed it here on s.e.d., >>>>>> complete with measurements, waveforms, detailed physics >>>>>> paper references and the works. Nailed it down. As it >>>>>> happens, the jitterbug analogy isn't so far off. >>>>> >>>>> Those are some nice threads, I went back and read them a few years >>>>> ago. Turning lemons into lemonade, a 20V zener baised at ~10uA >>>>> makes a nice noise source out to ~100's of kHz. >>>>> >>>>> I've also been reading Hamamatsu app notes on their Silicon PMT. >>>>> Which is really a Si avalanche photodiode in "Geiger-mode" >>>>> (biased above the breakdown voltage.) Fun stuff. >>>>> >>>>> George H. >>>> >>>> I'm in conversation with a big biosci company about cost-reducing their >>>> detection subsystems, so this has come up a lot lately. "Si PMTs" are >>>> basically an array of APDs wired in parallel and run in Geiger mode. >>>> The idea is that having multiple pixels allows you to extend Geiger mode >>>> to pulses containing more photons without losing resolution. >>>> >>>> AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when >>>> uniformly illuminated they start to become nonlinear at depressingly low >>>> photon numbers--the linearity error is 10% once 10% of the pixels have >>>> fired, because only 90% are available. >>>> >>>> You can apply a correction for this that might work adequately up to >>>> about 25%, but it starts to run out of gas pretty fast compared with a >>>> real PMT. Their dynamic range requirements were much too large for this >>>> to work for them. >>>> >>>> Also the dark counts are ridiculously worse--more than 10**6 times worse >>>> on an area basis. >>>> >>>> The real advantage of MPPCs is that you can do thresholding, which helps >>>> reject single-pixel events at the expense of sensitivity. That reduces >>>> the effective dark count rate by a lot. >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> >>> If your customer is gigantic enough, maybe Hamamatsu would sell them >>> the cute little MEMS PMTs. >> >> Wouldn't that be nice! Of course the designer has probably died of old >> age by now.... >> >> Cheers >> >> Phil Hobbs > > One cool idea is to use a microchannel plate in front of a 2D > delay-line detector. That can log the X-Y-T hits of single electrons > or photons at a pretty high rate. > > My only patent is for a delay-line detector, US7019307. Yeah, I haven't filed one since I left IBM. They cost money, and I couldn't afford to defend it anyway. Hopefully after this year I'll have more leisure to work on stuff of interest to me personally. We'll see. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-05-23 09:06 -0700 |
| Message-ID | <19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com> |
| In reply to | #461356 |
On Tue, 23 May 2017 10:40:49 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >On 05/23/2017 12:07 AM, John Larkin wrote: >> On Mon, 22 May 2017 15:57:13 -0400, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> On 05/22/2017 03:48 PM, John Larkin wrote: >>>> On Mon, 22 May 2017 15:12:20 -0400, Phil Hobbs >>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>> >>>>> On 05/22/2017 10:33 AM, George Herold wrote: >>>>>> On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: >>>>>>> Cursitor Doom wrote... >>>>>>>> >>>>>>>> Jim Thompson wrote: >>>>>>>> >>>>>>>>> AKA Flicker Noise >>>>>>>> >>>>>>>> Yup, pink noise. No jittering/jitterbugging involved. ;) >>>>>>> >>>>>>> Actually, I'd say you're wrong. The zener noise that we >>>>>>> see in avalanche mode (greater then 7 volts or so) is due >>>>>>> to step-wise "microplasma" ns-scale changes in current. >>>>>>> A decade or so ago we fully discussed it here on s.e.d., >>>>>>> complete with measurements, waveforms, detailed physics >>>>>>> paper references and the works. Nailed it down. As it >>>>>>> happens, the jitterbug analogy isn't so far off. >>>>>> >>>>>> Those are some nice threads, I went back and read them a few years >>>>>> ago. Turning lemons into lemonade, a 20V zener baised at ~10uA >>>>>> makes a nice noise source out to ~100's of kHz. >>>>>> >>>>>> I've also been reading Hamamatsu app notes on their Silicon PMT. >>>>>> Which is really a Si avalanche photodiode in "Geiger-mode" >>>>>> (biased above the breakdown voltage.) Fun stuff. >>>>>> >>>>>> George H. >>>>> >>>>> I'm in conversation with a big biosci company about cost-reducing their >>>>> detection subsystems, so this has come up a lot lately. "Si PMTs" are >>>>> basically an array of APDs wired in parallel and run in Geiger mode. >>>>> The idea is that having multiple pixels allows you to extend Geiger mode >>>>> to pulses containing more photons without losing resolution. >>>>> >>>>> AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when >>>>> uniformly illuminated they start to become nonlinear at depressingly low >>>>> photon numbers--the linearity error is 10% once 10% of the pixels have >>>>> fired, because only 90% are available. >>>>> >>>>> You can apply a correction for this that might work adequately up to >>>>> about 25%, but it starts to run out of gas pretty fast compared with a >>>>> real PMT. Their dynamic range requirements were much too large for this >>>>> to work for them. >>>>> >>>>> Also the dark counts are ridiculously worse--more than 10**6 times worse >>>>> on an area basis. >>>>> >>>>> The real advantage of MPPCs is that you can do thresholding, which helps >>>>> reject single-pixel events at the expense of sensitivity. That reduces >>>>> the effective dark count rate by a lot. >>>>> >>>>> Cheers >>>>> >>>>> Phil Hobbs >>>> >>>> If your customer is gigantic enough, maybe Hamamatsu would sell them >>>> the cute little MEMS PMTs. >>> >>> Wouldn't that be nice! Of course the designer has probably died of old >>> age by now.... >>> >>> Cheers >>> >>> Phil Hobbs >> >> One cool idea is to use a microchannel plate in front of a 2D >> delay-line detector. That can log the X-Y-T hits of single electrons >> or photons at a pretty high rate. >> >> My only patent is for a delay-line detector, US7019307. > >Yeah, I haven't filed one since I left IBM. They cost money, and I >couldn't afford to defend it anyway. > I think I got that one after a short brainstorming session with Tye. Imago was in the VC/file-lots-of-patents phase, so they filed it. I discovered the patent accidentally during a web search. I suppose I signed something at some point, but I'd forgotten. https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG If you let the electron cloud expand a bit before it hits the delay lines, you can filter and interpolate, and get X-Y resolution of a small fraction of the line pitch. http://www.cameca.com/image.asbx?AttributeFileId=dd44ee36-708e-4cb5-8313-6c5ce95e8c66 Those dots are single atoms in a 3D reconstruction. >Hopefully after this year I'll have more leisure to work on stuff of >interest to me personally. We'll see. > >Cheers > >Phil Hobbs Have some fun! -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> |
|---|---|
| Date | 2017-05-23 12:12 -0400 |
| Message-ID | <36e2cda4-21a8-b6c2-6b05-c955d2eb8f51@electrooptical.net> |
| In reply to | #461371 |
On 05/23/2017 12:06 PM, John Larkin wrote: > On Tue, 23 May 2017 10:40:49 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 05/23/2017 12:07 AM, John Larkin wrote: >>> On Mon, 22 May 2017 15:57:13 -0400, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> On 05/22/2017 03:48 PM, John Larkin wrote: >>>>> On Mon, 22 May 2017 15:12:20 -0400, Phil Hobbs >>>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>>> >>>>>> On 05/22/2017 10:33 AM, George Herold wrote: >>>>>>> On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: >>>>>>>> Cursitor Doom wrote... >>>>>>>>> >>>>>>>>> Jim Thompson wrote: >>>>>>>>> >>>>>>>>>> AKA Flicker Noise >>>>>>>>> >>>>>>>>> Yup, pink noise. No jittering/jitterbugging involved. ;) >>>>>>>> >>>>>>>> Actually, I'd say you're wrong. The zener noise that we >>>>>>>> see in avalanche mode (greater then 7 volts or so) is due >>>>>>>> to step-wise "microplasma" ns-scale changes in current. >>>>>>>> A decade or so ago we fully discussed it here on s.e.d., >>>>>>>> complete with measurements, waveforms, detailed physics >>>>>>>> paper references and the works. Nailed it down. As it >>>>>>>> happens, the jitterbug analogy isn't so far off. >>>>>>> >>>>>>> Those are some nice threads, I went back and read them a few years >>>>>>> ago. Turning lemons into lemonade, a 20V zener baised at ~10uA >>>>>>> makes a nice noise source out to ~100's of kHz. >>>>>>> >>>>>>> I've also been reading Hamamatsu app notes on their Silicon PMT. >>>>>>> Which is really a Si avalanche photodiode in "Geiger-mode" >>>>>>> (biased above the breakdown voltage.) Fun stuff. >>>>>>> >>>>>>> George H. >>>>>> >>>>>> I'm in conversation with a big biosci company about cost-reducing their >>>>>> detection subsystems, so this has come up a lot lately. "Si PMTs" are >>>>>> basically an array of APDs wired in parallel and run in Geiger mode. >>>>>> The idea is that having multiple pixels allows you to extend Geiger mode >>>>>> to pulses containing more photons without losing resolution. >>>>>> >>>>>> AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when >>>>>> uniformly illuminated they start to become nonlinear at depressingly low >>>>>> photon numbers--the linearity error is 10% once 10% of the pixels have >>>>>> fired, because only 90% are available. >>>>>> >>>>>> You can apply a correction for this that might work adequately up to >>>>>> about 25%, but it starts to run out of gas pretty fast compared with a >>>>>> real PMT. Their dynamic range requirements were much too large for this >>>>>> to work for them. >>>>>> >>>>>> Also the dark counts are ridiculously worse--more than 10**6 times worse >>>>>> on an area basis. >>>>>> >>>>>> The real advantage of MPPCs is that you can do thresholding, which helps >>>>>> reject single-pixel events at the expense of sensitivity. That reduces >>>>>> the effective dark count rate by a lot. >>>>>> >>>>>> Cheers >>>>>> >>>>>> Phil Hobbs >>>>> >>>>> If your customer is gigantic enough, maybe Hamamatsu would sell them >>>>> the cute little MEMS PMTs. >>>> >>>> Wouldn't that be nice! Of course the designer has probably died of old >>>> age by now.... >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> >>> One cool idea is to use a microchannel plate in front of a 2D >>> delay-line detector. That can log the X-Y-T hits of single electrons >>> or photons at a pretty high rate. >>> >>> My only patent is for a delay-line detector, US7019307. >> >> Yeah, I haven't filed one since I left IBM. They cost money, and I >> couldn't afford to defend it anyway. >> > > I think I got that one after a short brainstorming session with Tye. > Imago was in the VC/file-lots-of-patents phase, so they filed it. I > discovered the patent accidentally during a web search. I suppose I > signed something at some point, but I'd forgotten. > > https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG > > If you let the electron cloud expand a bit before it hits the delay > lines, you can filter and interpolate, and get X-Y resolution of a > small fraction of the line pitch. > > http://www.cameca.com/image.asbx?AttributeFileId=dd44ee36-708e-4cb5-8313-6c5ce95e8c66 > > Those dots are single atoms in a 3D reconstruction. > > >> Hopefully after this year I'll have more leisure to work on stuff of >> interest to me personally. We'll see. >> > > Have some fun! Yup. I want to build more instruments and fewer TIAs. That's one reason for offering TIAs and noise cancellers for sale. I'm also hoping to offer a super-wideband temperature control system at some point--the proto works okay. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
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| From | Jan Panteltje <pNa0nStpealmtje@yahoo.com> |
|---|---|
| Date | 2017-05-23 17:46 +0000 |
| Message-ID | <og1sgt$1cjj$1@gioia.aioe.org> |
| In reply to | #461371 |
On a sunny day (Tue, 23 May 2017 09:06:06 -0700) it happened John Larkin <jjlarkin@highlandtechnology.com> wrote in <19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com>: >I think I got that one after a short brainstorming session with Tye. >Imago was in the VC/file-lots-of-patents phase, so they filed it. I >discovered the patent accidentally during a web search. I suppose I >signed something at some point, but I'd forgotten. > >https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG No idea how it works but it does remind me of a rear-window heater,
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| From | John Larkin <jjlarkin@highland_snip_technology.com> |
|---|---|
| Date | 2017-05-23 11:18 -0700 |
| Message-ID | <s0v8icl0730vbu3sflob86gmp3mumqmv97@4ax.com> |
| In reply to | #461395 |
On Tue, 23 May 2017 17:46:05 GMT, Jan Panteltje <pNa0nStpealmtje@yahoo.com> wrote: >On a sunny day (Tue, 23 May 2017 09:06:06 -0700) it happened John Larkin ><jjlarkin@highlandtechnology.com> wrote in ><19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com>: > >>I think I got that one after a short brainstorming session with Tye. >>Imago was in the VC/file-lots-of-patents phase, so they filed it. I >>discovered the patent accidentally during a web search. I suppose I >>signed something at some point, but I'd forgotten. >> >>https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG > >No idea how it works but it does remind me of a rear-window heater, This explains the delay-line detector idea pretty well. www.chem.ucla.edu/~michalet/papers/IEEE2005.pdf The tomographic atom probe rips a sample apart one atom at a time and measures the XY position and time-of-flight, to reconstruct a 3D image of a sample. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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| From | Jan Panteltje <pNa0nStpealmtje@yahoo.com> |
|---|---|
| Date | 2017-05-23 19:35 +0000 |
| Message-ID | <og22ua$1odr$1@gioia.aioe.org> |
| In reply to | #461402 |
On a sunny day (Tue, 23 May 2017 11:18:57 -0700) it happened John Larkin <jjlarkin@highland_snip_technology.com> wrote in <s0v8icl0730vbu3sflob86gmp3mumqmv97@4ax.com>: >On Tue, 23 May 2017 17:46:05 GMT, Jan Panteltje ><pNa0nStpealmtje@yahoo.com> wrote: > >>On a sunny day (Tue, 23 May 2017 09:06:06 -0700) it happened John Larkin >><jjlarkin@highlandtechnology.com> wrote in >><19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com>: >> >>>I think I got that one after a short brainstorming session with Tye. >>>Imago was in the VC/file-lots-of-patents phase, so they filed it. I >>>discovered the patent accidentally during a web search. I suppose I >>>signed something at some point, but I'd forgotten. >>> >>>https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG >> >>No idea how it works but it does remind me of a rear-window heater, > >This explains the delay-line detector idea pretty well. > >www.chem.ucla.edu/~michalet/papers/IEEE2005.pdf > >The tomographic atom probe rips a sample apart one atom at a time and >measures the XY position and time-of-flight, to reconstruct a 3D image >of a sample. Very interesting concept. Using x and y delay lines, had not seen that one before. Thanks
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-05-23 21:18 -0700 |
| Message-ID | <v22aic95vjaajp5asr54h6bg3ue3i42g0n@4ax.com> |
| In reply to | #461415 |
On Tue, 23 May 2017 19:35:38 GMT, Jan Panteltje <pNa0nStpealmtje@yahoo.com> wrote: >On a sunny day (Tue, 23 May 2017 11:18:57 -0700) it happened John Larkin ><jjlarkin@highland_snip_technology.com> wrote in ><s0v8icl0730vbu3sflob86gmp3mumqmv97@4ax.com>: > >>On Tue, 23 May 2017 17:46:05 GMT, Jan Panteltje >><pNa0nStpealmtje@yahoo.com> wrote: >> >>>On a sunny day (Tue, 23 May 2017 09:06:06 -0700) it happened John Larkin >>><jjlarkin@highlandtechnology.com> wrote in >>><19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com>: >>> >>>>I think I got that one after a short brainstorming session with Tye. >>>>Imago was in the VC/file-lots-of-patents phase, so they filed it. I >>>>discovered the patent accidentally during a web search. I suppose I >>>>signed something at some point, but I'd forgotten. >>>> >>>>https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG >>> >>>No idea how it works but it does remind me of a rear-window heater, >> >>This explains the delay-line detector idea pretty well. >> >>www.chem.ucla.edu/~michalet/papers/IEEE2005.pdf >> >>The tomographic atom probe rips a sample apart one atom at a time and >>measures the XY position and time-of-flight, to reconstruct a 3D image >>of a sample. > >Very interesting concept. >Using x and y delay lines, had not seen that one before. >Thanks There's also an imaging technique, also used with microchannel plates, that uses resistive charge distribution to get the X-Y coordinates, based on amplitudes instead of time. There are fun things you can do with the delay-line imager, like crosscheck timings to untangle multiple-particle pileups and such. You could probably make a 2D delay line with optical fibers instead of conductors. Much less loss. -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Jan Panteltje <pNa0nStpealmtje@yahoo.com> |
|---|---|
| Date | 2017-05-24 16:35 +0000 |
| Message-ID | <og4cp6$1hrl$1@gioia.aioe.org> |
| In reply to | #461496 |
On a sunny day (Tue, 23 May 2017 21:18:14 -0700) it happened John Larkin <jjlarkin@highlandtechnology.com> wrote in <v22aic95vjaajp5asr54h6bg3ue3i42g0n@4ax.com>: >On Tue, 23 May 2017 19:35:38 GMT, Jan Panteltje ><pNa0nStpealmtje@yahoo.com> wrote: > >>On a sunny day (Tue, 23 May 2017 11:18:57 -0700) it happened John Larkin >><jjlarkin@highland_snip_technology.com> wrote in >><s0v8icl0730vbu3sflob86gmp3mumqmv97@4ax.com>: >> >>>On Tue, 23 May 2017 17:46:05 GMT, Jan Panteltje >>><pNa0nStpealmtje@yahoo.com> wrote: >>> >>>>On a sunny day (Tue, 23 May 2017 09:06:06 -0700) it happened John Larkin >>>><jjlarkin@highlandtechnology.com> wrote in >>>><19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com>: >>>> >>>>>I think I got that one after a short brainstorming session with Tye. >>>>>Imago was in the VC/file-lots-of-patents phase, so they filed it. I >>>>>discovered the patent accidentally during a web search. I suppose I >>>>>signed something at some point, but I'd forgotten. >>>>> >>>>>https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG >>>> >>>>No idea how it works but it does remind me of a rear-window heater, >>> >>>This explains the delay-line detector idea pretty well. >>> >>>www.chem.ucla.edu/~michalet/papers/IEEE2005.pdf >>> >>>The tomographic atom probe rips a sample apart one atom at a time and >>>measures the XY position and time-of-flight, to reconstruct a 3D image >>>of a sample. >> >>Very interesting concept. >>Using x and y delay lines, had not seen that one before. >>Thanks > >There's also an imaging technique, also used with microchannel plates, >that uses resistive charge distribution to get the X-Y coordinates, >based on amplitudes instead of time. > >There are fun things you can do with the delay-line imager, like >crosscheck timings to untangle multiple-particle pileups and such. > >You could probably make a 2D delay line with optical fibers instead of >conductors. Much less loss. In 1973 or there about when I worked in the TV studio, one of the engineers came to me with a an enlarged microfilm of a patent for a video recorder and asked me if I could make any sense of it. It was given to him by the local electronics shop. Video recording was my field there. The system had a name, cannot remember, will let you know if it comes back to me. That patent used one vertical oriented delay line that put charge on a vinyl tape that moved passed it, that way recording the charge pattern (image). I could not say it was wrong, but told him it was in my view not very likely that charge patterns would stay intact on a rolled up vinyl tape for any length of time. That idea never made it to market AFAIK.
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-05-25 08:12 -0700 |
| Message-ID | <51tdicptm2lhskrpasur2j4b3gtermn2mm@4ax.com> |
| In reply to | #461555 |
On Wed, 24 May 2017 16:35:49 GMT, Jan Panteltje <pNa0nStpealmtje@yahoo.com> wrote: >On a sunny day (Tue, 23 May 2017 21:18:14 -0700) it happened John Larkin ><jjlarkin@highlandtechnology.com> wrote in ><v22aic95vjaajp5asr54h6bg3ue3i42g0n@4ax.com>: > >>On Tue, 23 May 2017 19:35:38 GMT, Jan Panteltje >><pNa0nStpealmtje@yahoo.com> wrote: >> >>>On a sunny day (Tue, 23 May 2017 11:18:57 -0700) it happened John Larkin >>><jjlarkin@highland_snip_technology.com> wrote in >>><s0v8icl0730vbu3sflob86gmp3mumqmv97@4ax.com>: >>> >>>>On Tue, 23 May 2017 17:46:05 GMT, Jan Panteltje >>>><pNa0nStpealmtje@yahoo.com> wrote: >>>> >>>>>On a sunny day (Tue, 23 May 2017 09:06:06 -0700) it happened John Larkin >>>>><jjlarkin@highlandtechnology.com> wrote in >>>>><19m8ictl25ltljji98fp9m0854cvrgpp86@4ax.com>: >>>>> >>>>>>I think I got that one after a short brainstorming session with Tye. >>>>>>Imago was in the VC/file-lots-of-patents phase, so they filed it. I >>>>>>discovered the patent accidentally during a web search. I suppose I >>>>>>signed something at some point, but I'd forgotten. >>>>>> >>>>>>https://dl.dropboxusercontent.com/u/53724080/Gear/Anodes.JPG >>>>> >>>>>No idea how it works but it does remind me of a rear-window heater, >>>> >>>>This explains the delay-line detector idea pretty well. >>>> >>>>www.chem.ucla.edu/~michalet/papers/IEEE2005.pdf >>>> >>>>The tomographic atom probe rips a sample apart one atom at a time and >>>>measures the XY position and time-of-flight, to reconstruct a 3D image >>>>of a sample. >>> >>>Very interesting concept. >>>Using x and y delay lines, had not seen that one before. >>>Thanks >> >>There's also an imaging technique, also used with microchannel plates, >>that uses resistive charge distribution to get the X-Y coordinates, >>based on amplitudes instead of time. >> >>There are fun things you can do with the delay-line imager, like >>crosscheck timings to untangle multiple-particle pileups and such. >> >>You could probably make a 2D delay line with optical fibers instead of >>conductors. Much less loss. > >In 1973 or there about when I worked in the TV studio, >one of the engineers came to me with a an enlarged microfilm of a patent >for a video recorder and asked me if I could make any sense of it. >It was given to him by the local electronics shop. >Video recording was my field there. >The system had a name, cannot remember, will let you know if it comes back to me. >That patent used one vertical oriented delay line that put charge on a vinyl tape >that moved passed it, that way recording the charge pattern (image). >I could not say it was wrong, but told him it was in my view not very likely >that charge patterns would stay intact on a rolled up vinyl tape for any length of time. >That idea never made it to market AFAIK. Did it heat the tape during recording? Possibly electret charging. -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Jan Panteltje <pNa0nStpealmtje@yahoo.com> |
|---|---|
| Date | 2017-05-25 15:24 +0000 |
| Message-ID | <og6sv6$18c9$1@gioia.aioe.org> |
| In reply to | #461663 |
On a sunny day (Thu, 25 May 2017 08:12:17 -0700) it happened John Larkin <jjlarkin@highlandtechnology.com> wrote in <51tdicptm2lhskrpasur2j4b3gtermn2mm@4ax.com>: >On Wed, 24 May 2017 16:35:49 GMT, Jan Panteltje ><pNa0nStpealmtje@yahoo.com> wrote: >>In 1973 or there about when I worked in the TV studio, >>one of the engineers came to me with a an enlarged microfilm of a patent >>for a video recorder and asked me if I could make any sense of it. >>It was given to him by the local electronics shop. >>Video recording was my field there. >>The system had a name, cannot remember, will let you know if it comes back to me. >>That patent used one vertical oriented delay line that put charge on a vinyl tape >>that moved passed it, that way recording the charge pattern (image). >>I could not say it was wrong, but told him it was in my view not very likely >>that charge patterns would stay intact on a rolled up vinyl tape for any length of time. >>That idea never made it to market AFAIK. > >Did it heat the tape during recording? Possibly electret charging. Not that I know.
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| From | Jan Panteltje <pNa0nStpealmtje@yahoo.com> |
|---|---|
| Date | 2017-05-25 07:40 +0000 |
| Message-ID | <og61q7$1ua5$1@gioia.aioe.org> |
| In reply to | #461496 |
> >In 1973 or there about when I worked in the TV studio, >one of the engineers came to me with a an enlarged microfilm of a patent >for a video recorder and asked me if I could make any sense of it. >It was given to him by the local electronics shop. >Video recording was my field there. >The system had a name, cannot remember, will let you know if it comes back to me. It was called 'Ventiel Raster Diode'. That was Dutch and translated means something like 'one way raster diode'. Googling gives zero hits. Maybe the tape was coated to prevent the charge leaking, was not very clear or complete. >That patent used one vertical oriented delay line that put charge on a vinyl tape >that moved passed it, that way recording the charge pattern (image). >I could not say it was wrong, but told him it was in my view not very likely >that charge patterns would stay intact on a rolled up vinyl tape for any length of time. >That idea never made it to market AFAIK. >
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| From | Clifford Heath <no.spam@please.net> |
|---|---|
| Date | 2017-05-25 17:44 +1000 |
| Message-ID | <pYvVA.48432$Cj6.25910@fx23.iad> |
| In reply to | #461630 |
On 25/05/17 17:40, Jan Panteltje wrote: > >> >> In 1973 or there about when I worked in the TV studio, >> one of the engineers came to me with a an enlarged microfilm of a patent >> for a video recorder and asked me if I could make any sense of it. >> It was given to him by the local electronics shop. >> Video recording was my field there. >> The system had a name, cannot remember, will let you know if it comes back to me. > > It was called 'Ventiel Raster Diode'. > That was Dutch and translated means something like 'one way raster diode'. > Googling gives zero hits. > Maybe the tape was coated to prevent the charge leaking, was not very clear or complete. Maybe it was called "one way" because you could record, but not play back?
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| From | Jan Panteltje <pNa0nStpealmtje@yahoo.com> |
|---|---|
| Date | 2017-05-25 07:52 +0000 |
| Message-ID | <og62f2$1v8m$1@gioia.aioe.org> |
| In reply to | #461632 |
On a sunny day (Thu, 25 May 2017 17:44:36 +1000) it happened Clifford Heath <no.spam@please.net> wrote in <pYvVA.48432$Cj6.25910@fx23.iad>: >On 25/05/17 17:40, Jan Panteltje wrote: >> >>> >>> In 1973 or there about when I worked in the TV studio, >>> one of the engineers came to me with a an enlarged microfilm of a patent >>> for a video recorder and asked me if I could make any sense of it. >>> It was given to him by the local electronics shop. >>> Video recording was my field there. >>> The system had a name, cannot remember, will let you know if it comes back to me. >> >> It was called 'Ventiel Raster Diode'. >> That was Dutch and translated means something like 'one way raster diode'. >> Googling gives zero hits. >> Maybe the tape was coated to prevent the charge leaking, was not very clear or complete. > >Maybe it was called "one way" because you could record, but not play back? Yes, that is it!
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| From | George Herold <gherold@teachspin.com> |
|---|---|
| Date | 2017-05-22 13:33 -0700 |
| Message-ID | <530dedf9-37f0-4e00-8c63-9f2532c9b2d7@googlegroups.com> |
| In reply to | #461285 |
On Monday, May 22, 2017 at 3:12:32 PM UTC-4, Phil Hobbs wrote: > On 05/22/2017 10:33 AM, George Herold wrote: > > On Sunday, May 21, 2017 at 8:10:45 PM UTC-4, Winfield Hill wrote: > >> Cursitor Doom wrote... > >>> > >>> Jim Thompson wrote: > >>> > >>>> AKA Flicker Noise > >>> > >>> Yup, pink noise. No jittering/jitterbugging involved. ;) > >> > >> Actually, I'd say you're wrong. The zener noise that we > >> see in avalanche mode (greater then 7 volts or so) is due > >> to step-wise "microplasma" ns-scale changes in current. > >> A decade or so ago we fully discussed it here on s.e.d., > >> complete with measurements, waveforms, detailed physics > >> paper references and the works. Nailed it down. As it > >> happens, the jitterbug analogy isn't so far off. > > > > Those are some nice threads, I went back and read them a few years > > ago. Turning lemons into lemonade, a 20V zener baised at ~10uA > > makes a nice noise source out to ~100's of kHz. > > > > I've also been reading Hamamatsu app notes on their Silicon PMT. > > Which is really a Si avalanche photodiode in "Geiger-mode" > > (biased above the breakdown voltage.) Fun stuff. > > > > George H. > > I'm in conversation with a big biosci company about cost-reducing their > detection subsystems, so this has come up a lot lately. "Si PMTs" are > basically an array of APDs wired in parallel and run in Geiger mode. > The idea is that having multiple pixels allows you to extend Geiger mode > to pulses containing more photons without losing resolution. > > AFAIK the biggest ones are about 120x120 pixels. Trouble is, even when > uniformly illuminated they start to become nonlinear at depressingly low > photon numbers--the linearity error is 10% once 10% of the pixels have > fired, because only 90% are available. > > You can apply a correction for this that might work adequately up to > about 25%, but it starts to run out of gas pretty fast compared with a > real PMT. Their dynamic range requirements were much too large for this > to work for them. > > Also the dark counts are ridiculously worse--more than 10**6 times worse > on an area basis. > > The real advantage of MPPCs is that you can do thresholding, which helps > reject single-pixel events at the expense of sensitivity. That reduces > the effective dark count rate by a lot. The only app I would have at the moment is doing Bell inequality experiments with ~800 nm correlated photons. (I don't really know all the details of the experiment.) So I don't think I'd care about linearity. All the small pixels means smaller gain, as each photon triggers a smaller capacitance discharge. George H. > > Cheers > > Phil Hobbs > > > -- > Dr Philip C D Hobbs > Principal Consultant > ElectroOptical Innovations LLC > Optics, Electro-optics, Photonics, Analog Electronics > > 160 North State Road #203 > Briarcliff Manor NY 10510 > > hobbs at electrooptical dot net > http://electrooptical.net
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| From | "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> |
|---|---|
| Date | 2017-05-27 15:53 -0400 |
| Message-ID | <ogclgl$1i6m$1@gioia.aioe.org> |
| In reply to | #461208 |
Winfield Hill wrote: > Cursitor Doom wrote... >> >> Jim Thompson wrote: >> >>> AKA Flicker Noise >> >> Yup, pink noise. No jittering/jitterbugging involved. ;) > > Actually, I'd say you're wrong. The zener noise that we > see in avalanche mode (greater then 7 volts or so) is due > to step-wise "microplasma" ns-scale changes in current. > A decade or so ago we fully discussed it here on s.e.d., > complete with measurements, waveforms, detailed physics > paper references and the works. Nailed it down. As it > happens, the jitterbug analogy isn't so far off. > > This avalanche jitterbug noise source is not available > in the low-voltage field emission zener operating mode, > so using two sub-6-volt zeners in series in place of a > higher-voltage zener, or any of many other good schemes > would indeed be a good idea. Is the low-voltage noise less than half, so it won't add up to more?
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| From | Winfield Hill <hill@rowland.harvard.edu> |
|---|---|
| Date | 2017-05-27 19:15 -0700 |
| Message-ID | <ogdbso02b2u@drn.newsguy.com> |
| In reply to | #462014 |
Tom Del Rosso wrote...
>
>Winfield Hill wrote:
>> Cursitor Doom wrote...
>>>
>>> Jim Thompson wrote:
>>>
>>>> AKA Flicker Noise
>>>
>>> Yup, pink noise. No jittering/jitterbugging involved. ;)
>>
>> Actually, I'd say you're wrong. The zener noise that we
>> see in avalanche mode (greater then 7 volts or so) is due
>> to step-wise "microplasma" ns-scale changes in current.
>> A decade or so ago we fully discussed it here on s.e.d.,
>> complete with measurements, waveforms, detailed physics
>> paper references and the works. Nailed it down. As it
>> happens, the jitterbug analogy isn't so far off.
>>
>> This avalanche jitterbug noise source is not available
>> in the low-voltage field emission zener operating mode,
>> so using two sub-6-volt zeners in series in place of a
>> higher-voltage zener, or any of many other good schemes
>> would indeed be a good idea.
>
> Is the low-voltage noise less than half, so it
> won't add up to more?
Yes, it's a tiny fraction. Try it.
--
Thanks,
- Win
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| From | "Tim Williams" <tiwill@seventransistorlabs.com> |
|---|---|
| Date | 2017-05-21 11:29 -0500 |
| Message-ID | <ofsf36$44h$1@dont-email.me> |
| In reply to | #461110 |
Take away their coffee. Tim -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website: http://seventransistorlabs.com "Chris" <cbx@noreply.com> wrote in message news:ofrsc3$5em$2@dont-email.me... > Has anyone got any suggestions as to how to best deal with the phenomenon > of jittering zeners? Preferably without adding excessive complexity to a > circuit, I mean.
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