On Wednesday, September 11, 2019 at 4:16:51 PM UTC-4, George Herold wrote:
> On Wednesday, September 4, 2019 at 1:45:09 PM UTC-4, George Herold wrote:
> > Hi all, Well the opa124 is EOL, suggested replacement is opa145.  
> > http://www.ti.com/lit/ds/symlink/opa145.pdf
> > Looks nice.  Very low 1/f noise corner.  And then I got a little worried 
> > looking a figure 17, which shows voltage noise rising from 10k Hz on.. and then
> > the graph ends at 100 kHz.  
> > 
> > Anyone looked at used this opamp?  
> > I'm going to order a few.  
> > 
> > Thx
> > George H.
> 
> Well indeed the oap145 has voltage noise that rises by about 6dB by 100kHz.  
> Though it appears to flatten off there and not go any higher.  
> 
> Folder with 'scope Q-FFT's and SRS 730, these pics are a bit cryptic and 
> I'd have to explain them... well the srs one is fairly obvious.
> 
> George H.  
> 
> https://www.dropbox.com/sh/bl38w9o1gdpqq4x/AADSaSuLdHW8mgpfYOADqbzPa?dl=0

 Dang you can't see those 'scope displays at all.  
(John L. how do you take such nice screen shots?)
So for me, the 1MHz Q-fft* The fft is 4 dB per div, 
500 kHz span and 250 (246?) kHz center freq.  
(The noise looks to peak/ flatten at 150-200kHz.)
 
100kHz band width is noise into same up stream amp but with 
100kHz 2-pole, ~Q=0.707 LP filter. 
10 dB/ div.  Same freq scale.

The SRS is it's max BW 0-100kHz and ~1000 averages
(the Q-fft are also 1024 averages.)

George H. 
(*with a Q-fft you have to divide the power scale in half. 
you can do the math, or check it with a known filter
and a noise source.) (my colleague 'did the math' for me..
I can post the relevant section of the manual if anyone wants.) 
And there is an interesting question with how small a coherent 
signal you can see.. 'buried in the noise' say in some given time.
(to make a Qfft you've got to trigger near the top of your 
noise + small signal.. you get more 'small signal' triggers 
with a higher trigger level, but less number of traces to average.
Does it go as the time squared, compared to a system that 
does the FFT and then averages that?  


 

On Wednesday, September 4, 2019 at 1:45:09 PM UTC-4, George Herold wrote:
> Hi all, Well the opa124 is EOL, suggested replacement is opa145.  
> http://www.ti.com/lit/ds/symlink/opa145.pdf
> Looks nice.  Very low 1/f noise corner.  And then I got a little worried 
> looking a figure 17, which shows voltage noise rising from 10k Hz on.. and then
> the graph ends at 100 kHz.  
> 
> Anyone looked at used this opamp?  
> I'm going to order a few.  
> 
> Thx
> George H.

Well indeed the oap145 has voltage noise that rises by about 6dB by 100kHz.  
Though it appears to flatten off there and not go any higher.  

Folder with 'scope Q-FFT's and SRS 730, these pics are a bit cryptic and 
I'd have to explain them... well the srs one is fairly obvious.

George H.  

https://www.dropbox.com/sh/bl38w9o1gdpqq4x/AADSaSuLdHW8mgpfYOADqbzPa?dl=0

 

On Friday, September 6, 2019 at 3:33:09 PM UTC-4, John Larkin wrote:
> On Fri, 6 Sep 2019 15:11:33 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> 
> >On 9/6/19 1:03 PM, John Larkin wrote:
> >> On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
> >> <gherold@teachspin.com> wrote:
> >> 
> >>> On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
> >>>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
> >>>> <gherold@teachspin.com> wrote:
> >>>>
> >>>>> On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
> >>>>>> George Herold wrote...
> >>>>>>>
> >>>>>>> So this is a bit of an aside, but I need a new gig*.
> >>>>>>
> >>>>>>   What's wrong with your present gig?  You seem to be
> >>>>>>   doing well, doing interesting designs and helping to
> >>>>>>   create new teaching products, what's wrong with that?
> >>>>> Yeah on paper it's my perfect gig.
> >>>>> In practice... I guess we have to be talking person to
> >>>>> person, for the dirty laundry to be discussed.
> >>>>> The bottom line is that almost all my present day
> >>>>> collaboration, happens here (SED) and not at work.
> >>>>> Which sucks*.  I need a job where I look forward to
> >>>>> going into work each day, for reasons that are ~1/2 my
> >>>>> fault, that's not true anymore.
> >>>>>
> >>>>> George H.
> >>>>>
> >>>>>
> >>>>> *there's a double suckage, that goes with leaving,
> >>>>> and knowing things will be worse for all the
> >>>>> friends and coworkers left behind.
> >>>>> They are all friends and will understand,
> >>>>> but the double suckage remains.
> >>>>> GH
> >>>>
> >>>> I didn't have such a dilemma. I got fired.
> >>>
> >>> Hah, I got fired too!  we'll we need bar stools to
> >>> discuss the details.
> >>>
> >>> Maybe just a delayed fuse on my part.
> >>>
> >>> George h.
> >> 
> >> Being fired was great. Started my life over.
> >> 
> >
> >Mine too.
> >
> >Cheers
> >
> >Phil Hobbs
> 
> I designed $200M worth of electronics for them, and then they fired me
> for insubordination. The idiots didn't understand that engineers are
> supposed to be insubordinate.

As soon as I get a new gig I can talk 'on the air'.

So let me ask you this, we're bringing in phd's for a hire,
my inclination is tell them my situation, after which I'm 
totally fine with them taking the job.  
(but could scare 'em off... cause no one wants to 
maintain my old circuits, including me. :^)

George H. 

On Friday, September 6, 2019 at 3:11:40 PM UTC-4, Phil Hobbs wrote:
> On 9/6/19 1:03 PM, John Larkin wrote:
> > On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
> > <gherold@teachspin.com> wrote:
> > 
> >> On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
> >>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
> >>> <gherold@teachspin.com> wrote:
> >>>
> >>>> On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
> >>>>> George Herold wrote...
> >>>>>>
> >>>>>> So this is a bit of an aside, but I need a new gig*.
> >>>>>
> >>>>>   What's wrong with your present gig?  You seem to be
> >>>>>   doing well, doing interesting designs and helping to
> >>>>>   create new teaching products, what's wrong with that?
> >>>> Yeah on paper it's my perfect gig.
> >>>> In practice... I guess we have to be talking person to
> >>>> person, for the dirty laundry to be discussed.
> >>>> The bottom line is that almost all my present day
> >>>> collaboration, happens here (SED) and not at work.
> >>>> Which sucks*.  I need a job where I look forward to
> >>>> going into work each day, for reasons that are ~1/2 my
> >>>> fault, that's not true anymore.
> >>>>
> >>>> George H.
> >>>>
> >>>>
> >>>> *there's a double suckage, that goes with leaving,
> >>>> and knowing things will be worse for all the
> >>>> friends and coworkers left behind.
> >>>> They are all friends and will understand,
> >>>> but the double suckage remains.
> >>>> GH
> >>>
> >>> I didn't have such a dilemma. I got fired.
> >>
> >> Hah, I got fired too!  we'll we need bar stools to
> >> discuss the details.
> >>
> >> Maybe just a delayed fuse on my part.
> >>
> >> George h.
> > 
> > Being fired was great. Started my life over.
> > 
> 
> Mine too.
Right,  that's what it feels like. 
I've always been a late bloomer so my mid life 
crisis can be a bit late at 60. :^) 

If you are not working for yourself, 
then its's a matter of finding the right boss.  
(who wants you.)

The worst part will be separation from my current 
place of employment, I really hate conflict.

I've always wanted to be the 'lab guy' at some 
college/ uni. which are 'liberal crazy*' these days,
and I sorta shudder at having to conform.

George H. 

*crazy = authoritarian


> 
> Cheers
> 
> Phil Hobbs
> 
> -- 
> Dr Philip C D Hobbs
> Principal Consultant
> ElectroOptical Innovations LLC / Hobbs ElectroOptics
> Optics, Electro-optics, Photonics, Analog Electronics
> Briarcliff Manor NY 10510
> 
> http://electrooptical.net
> http://hobbs-eo.com

On Fri, 6 Sep 2019 20:46:38 +0100, Tom Gardner
<spamjunk@blueyonder.co.uk> wrote:

>On 06/09/19 20:33, John Larkin wrote:
>> On Fri, 6 Sep 2019 15:11:33 -0400, Phil Hobbs
>> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>> 
>>> On 9/6/19 1:03 PM, John Larkin wrote:
>>>> On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
>>>> <gherold@teachspin.com> wrote:
>>>>
>>>>> On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
>>>>>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
>>>>>> <gherold@teachspin.com> wrote:
>>>>>>
>>>>>>> On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
>>>>>>>> George Herold wrote...
>>>>>>>>>
>>>>>>>>> So this is a bit of an aside, but I need a new gig*.
>>>>>>>>
>>>>>>>>    What's wrong with your present gig?  You seem to be
>>>>>>>>    doing well, doing interesting designs and helping to
>>>>>>>>    create new teaching products, what's wrong with that?
>>>>>>> Yeah on paper it's my perfect gig.
>>>>>>> In practice... I guess we have to be talking person to
>>>>>>> person, for the dirty laundry to be discussed.
>>>>>>> The bottom line is that almost all my present day
>>>>>>> collaboration, happens here (SED) and not at work.
>>>>>>> Which sucks*.  I need a job where I look forward to
>>>>>>> going into work each day, for reasons that are ~1/2 my
>>>>>>> fault, that's not true anymore.
>>>>>>>
>>>>>>> George H.
>>>>>>>
>>>>>>>
>>>>>>> *there's a double suckage, that goes with leaving,
>>>>>>> and knowing things will be worse for all the
>>>>>>> friends and coworkers left behind.
>>>>>>> They are all friends and will understand,
>>>>>>> but the double suckage remains.
>>>>>>> GH
>>>>>>
>>>>>> I didn't have such a dilemma. I got fired.
>>>>>
>>>>> Hah, I got fired too!  we'll we need bar stools to
>>>>> discuss the details.
>>>>>
>>>>> Maybe just a delayed fuse on my part.
>>>>>
>>>>> George h.
>>>>
>>>> Being fired was great. Started my life over.
>>>>
>>>
>>> Mine too.
>>>
>>> Cheers
>>>
>>> Phil Hobbs
>> 
>> I designed $200M worth of electronics for them, and then they fired me
>> for insubordination. The idiots didn't understand that engineers are
>> supposed to be insubordinate.
>
>Of course. Human resources are fungible. (Aren't they?)
>
>Whatever happened to the "personnel department"?

We don't have one.

On 06/09/19 20:33, John Larkin wrote:
> On Fri, 6 Sep 2019 15:11:33 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> 
>> On 9/6/19 1:03 PM, John Larkin wrote:
>>> On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
>>> <gherold@teachspin.com> wrote:
>>>
>>>> On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
>>>>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
>>>>> <gherold@teachspin.com> wrote:
>>>>>
>>>>>> On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
>>>>>>> George Herold wrote...
>>>>>>>>
>>>>>>>> So this is a bit of an aside, but I need a new gig*.
>>>>>>>
>>>>>>>    What's wrong with your present gig?  You seem to be
>>>>>>>    doing well, doing interesting designs and helping to
>>>>>>>    create new teaching products, what's wrong with that?
>>>>>> Yeah on paper it's my perfect gig.
>>>>>> In practice... I guess we have to be talking person to
>>>>>> person, for the dirty laundry to be discussed.
>>>>>> The bottom line is that almost all my present day
>>>>>> collaboration, happens here (SED) and not at work.
>>>>>> Which sucks*.  I need a job where I look forward to
>>>>>> going into work each day, for reasons that are ~1/2 my
>>>>>> fault, that's not true anymore.
>>>>>>
>>>>>> George H.
>>>>>>
>>>>>>
>>>>>> *there's a double suckage, that goes with leaving,
>>>>>> and knowing things will be worse for all the
>>>>>> friends and coworkers left behind.
>>>>>> They are all friends and will understand,
>>>>>> but the double suckage remains.
>>>>>> GH
>>>>>
>>>>> I didn't have such a dilemma. I got fired.
>>>>
>>>> Hah, I got fired too!  we'll we need bar stools to
>>>> discuss the details.
>>>>
>>>> Maybe just a delayed fuse on my part.
>>>>
>>>> George h.
>>>
>>> Being fired was great. Started my life over.
>>>
>>
>> Mine too.
>>
>> Cheers
>>
>> Phil Hobbs
> 
> I designed $200M worth of electronics for them, and then they fired me
> for insubordination. The idiots didn't understand that engineers are
> supposed to be insubordinate.

Of course. Human resources are fungible. (Aren't they?)

Whatever happened to the "personnel department"?

On Fri, 6 Sep 2019 15:11:33 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>On 9/6/19 1:03 PM, John Larkin wrote:
>> On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
>> <gherold@teachspin.com> wrote:
>> 
>>> On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
>>>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
>>>> <gherold@teachspin.com> wrote:
>>>>
>>>>> On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
>>>>>> George Herold wrote...
>>>>>>>
>>>>>>> So this is a bit of an aside, but I need a new gig*.
>>>>>>
>>>>>>   What's wrong with your present gig?  You seem to be
>>>>>>   doing well, doing interesting designs and helping to
>>>>>>   create new teaching products, what's wrong with that?
>>>>> Yeah on paper it's my perfect gig.
>>>>> In practice... I guess we have to be talking person to
>>>>> person, for the dirty laundry to be discussed.
>>>>> The bottom line is that almost all my present day
>>>>> collaboration, happens here (SED) and not at work.
>>>>> Which sucks*.  I need a job where I look forward to
>>>>> going into work each day, for reasons that are ~1/2 my
>>>>> fault, that's not true anymore.
>>>>>
>>>>> George H.
>>>>>
>>>>>
>>>>> *there's a double suckage, that goes with leaving,
>>>>> and knowing things will be worse for all the
>>>>> friends and coworkers left behind.
>>>>> They are all friends and will understand,
>>>>> but the double suckage remains.
>>>>> GH
>>>>
>>>> I didn't have such a dilemma. I got fired.
>>>
>>> Hah, I got fired too!  we'll we need bar stools to
>>> discuss the details.
>>>
>>> Maybe just a delayed fuse on my part.
>>>
>>> George h.
>> 
>> Being fired was great. Started my life over.
>> 
>
>Mine too.
>
>Cheers
>
>Phil Hobbs

I designed $200M worth of electronics for them, and then they fired me
for insubordination. The idiots didn't understand that engineers are
supposed to be insubordinate.

On 9/6/19 1:03 PM, John Larkin wrote:
> On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
> <gherold@teachspin.com> wrote:
> 
>> On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
>>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
>>> <gherold@teachspin.com> wrote:
>>>
>>>> On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
>>>>> George Herold wrote...
>>>>>>
>>>>>> So this is a bit of an aside, but I need a new gig*.
>>>>>
>>>>>   What's wrong with your present gig?  You seem to be
>>>>>   doing well, doing interesting designs and helping to
>>>>>   create new teaching products, what's wrong with that?
>>>> Yeah on paper it's my perfect gig.
>>>> In practice... I guess we have to be talking person to
>>>> person, for the dirty laundry to be discussed.
>>>> The bottom line is that almost all my present day
>>>> collaboration, happens here (SED) and not at work.
>>>> Which sucks*.  I need a job where I look forward to
>>>> going into work each day, for reasons that are ~1/2 my
>>>> fault, that's not true anymore.
>>>>
>>>> George H.
>>>>
>>>>
>>>> *there's a double suckage, that goes with leaving,
>>>> and knowing things will be worse for all the
>>>> friends and coworkers left behind.
>>>> They are all friends and will understand,
>>>> but the double suckage remains.
>>>> GH
>>>
>>> I didn't have such a dilemma. I got fired.
>>
>> Hah, I got fired too!  we'll we need bar stools to
>> discuss the details.
>>
>> Maybe just a delayed fuse on my part.
>>
>> George h.
> 
> Being fired was great. Started my life over.
> 

Mine too.

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Thu, 5 Sep 2019 18:08:29 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

>On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
>> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
>> <gherold@teachspin.com> wrote:
>> 
>> >On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
>> >> George Herold wrote...
>> >> >
>> >> > So this is a bit of an aside, but I need a new gig*.
>> >> 
>> >>  What's wrong with your present gig?  You seem to be
>> >>  doing well, doing interesting designs and helping to
>> >>  create new teaching products, what's wrong with that?
>> >Yeah on paper it's my perfect gig.
>> >In practice... I guess we have to be talking person to 
>> >person, for the dirty laundry to be discussed.
>> >The bottom line is that almost all my present day 
>> >collaboration, happens here (SED) and not at work.
>> >Which sucks*.  I need a job where I look forward to 
>> >going into work each day, for reasons that are ~1/2 my 
>> >fault, that's not true anymore.  
>> >
>> >George H. 
>> >
>> >
>> >*there's a double suckage, that goes with leaving, 
>> >and knowing things will be worse for all the 
>> >friends and coworkers left behind.
>> >They are all friends and will understand,
>> >but the double suckage remains. 
>> >GH 
>> 
>> I didn't have such a dilemma. I got fired.
>
>Hah, I got fired too!  we'll we need bar stools to 
>discuss the details.
>
>Maybe just a delayed fuse on my part.  
>
>George h. 

Being fired was great. Started my life over.

On Thursday, September 5, 2019 at 8:58:19 PM UTC-4, John Larkin wrote:
> On Thu, 5 Sep 2019 17:50:06 -0700 (PDT), George Herold
> <gherold@teachspin.com> wrote:
> 
> >On Thursday, September 5, 2019 at 5:36:55 PM UTC-4, Winfield Hill wrote:
> >> George Herold wrote...
> >> >
> >> > So this is a bit of an aside, but I need a new gig*.
> >> 
> >>  What's wrong with your present gig?  You seem to be
> >>  doing well, doing interesting designs and helping to
> >>  create new teaching products, what's wrong with that?
> >Yeah on paper it's my perfect gig.
> >In practice... I guess we have to be talking person to 
> >person, for the dirty laundry to be discussed.
> >The bottom line is that almost all my present day 
> >collaboration, happens here (SED) and not at work.
> >Which sucks*.  I need a job where I look forward to 
> >going into work each day, for reasons that are ~1/2 my 
> >fault, that's not true anymore.  
> >
> >George H. 
> >
> >
> >*there's a double suckage, that goes with leaving, 
> >and knowing things will be worse for all the 
> >friends and coworkers left behind.
> >They are all friends and will understand,
> >but the double suckage remains. 
> >GH 
> 
> I didn't have such a dilemma. I got fired.

Hah, I got fired too!  we'll we need bar stools to 
discuss the details.

Maybe just a delayed fuse on my part.  

George h.