SV: Re: SV: Re: [Fwd: Re: Op Amp pinouts was Re: [sdiy] more LM3900 stuff]

[karl dalen]

The latest thing i heard was "6 1/2 digits" 
and that was very good! 

HP has invented a way to calibrate it away! ;-)

http://www.uni-konstanz.de/physik/Jaeckle/papers/thermopower/node1.html

Anyhow it do sounds like what you say, sales talk!

REG
KD

--- Grant Richter <grichter at asapnet.net> skrev:

> Your in the range of thermoelectric voltages produce by differing  
> metals.
> I think they call it the "Seebeck effect".
> 
> Probably a chapter on it in the DVM manual.
> Must be some amazing common mode rejection to get rid of RF hash.
> 
> When I see figures like 0.00008% THD, I know it came from marketing  
> and not engineering.
> 
> I mean what is the X bar distribution on THD for practical  
> manufacturing?
> Can the process be controlled? Do they test for the THD spec?
> 
> Silly numbers stuff.
> 
> On Jan 21, 2006, at 6:28 PM, karl dalen wrote:
> 
> > Oh! Impressive!
> > ""8 1/2 digits with 10 nV DC resolution""!
> >
> > This is not any "off the shelf dual slope" ADC,ing thing!
> >
> > 10nV!! Slightest oxidation on a component
> > leg would ruin that i suppose! There must be
> > an entire manual of just cleansing legs before
> > measurements!
> >
> > KD
> >
> > --- Ian Fritz <ijfritz at earthlink.net> skrev:
> >
> >> At 12:01 PM 1/21/06, Ian Fritz wrote:
> >>> At 11:36 PM 1/20/06, Grant Richter wrote:
> >>>
> >>>>> Have you looked at the OPA134?  Distortion = .00008%
> >>>>
> >>>> How do you even measure that? A 24 bit sine wave is 0.001% THD
> >>>
> >>> I believe a 24 bit sine is better than that.  But, whatever, you  
> >>> can get a
> >>> DVM with enough precision:
> >>
> >> <http://www.home.agilent.com/cgi-bin/pub/agilent/Product/ 
> >> cp_Product.jsp? 
> >> LANGUAGE_CODE=eng&COUNTRY_CODE=US&NAV_ID=-11250.536881781.00&cmpid=96 
> >> 200>
> >>
> >>>
> >>
> >> Crap, that link has a timeout.  Just go to agilent.com and look up  
> >> the
> >> 3458A DVM.
> >>
> >>
> 
>