John Curl's Blowtorch preamplifier part II

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From data input and acquisition, to analysis and display, to reduction and manipulation, to transformation and what-if simulations, to publication-quality output for journals, reports and presentations: DADiSP does it all!

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DADiSP - Adept Scientific

It is not "profesional secrets", scientific surrounding is LabVIEW, Origin and Matlab.
And a tons of custom codes for various measurements.
 
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Wahab; Really? I thought it was pretty good at ANY level. The instrument bottoms out at -140... the monitor output into FFT (QA401) has to be used to tell how much lower than -140 it really is. Oh well. Back to the drawing board, I guess. You guys are hard to please.

:)
THx-RNMarsh
 
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I am involved in science over 30 years...as a tech support(tech advisor, lab mouse..:)), so, my informations is "first hand"..it is professional information, not a secret.
Tools for students and for PhD..
Open source is usable(and cheap), but for experimental verification, acceptable programs are necessary.
Some extremely complex experiments, like Cern installation, needs radically new approach, new clusters, custom software..
My 2,5 cents..:)
 
Gee I thought it was because there were Maxwell's demons one way and Checkered demons the other.

See you can learn things here. The trolls chased away the demons and are more efficient with just one way toll collections. You just aren't staying up to date.

BTY the checkered demon had a really bad motorcycle accident and get well cards are appreciated.

As you well know you can't put it on the internet unless it is true.
 
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Disabled Account
Joined 2012
I am involved in science over 30 years...as a tech support(tech advisor, lab mouse..:)), so, my informations is "first hand"..it is professional information, not a secret.
Tools for students and for PhD..
Open source is usable(and cheap), but for experimental verification, acceptable programs are necessary.
Some extremely complex experiments, like Cern installation, needs radically new approach, new clusters, custom software..
My 2,5 cents..:)

:cool::)


-RNM
 
Some extremely complex experiments, like Cern installation, needs radically new approach, new clusters, custom software..
My 2,5 cents..:)

It's still based on a free open source OS and in general I have found no signal processing algorithms that are not freely available, in fact in the distant past I have contributed (in a small way). For me part of DIY is the learning and I don't need canned ($$$) solutions.

CERN has taken the approach of a grid of thousands of compute nodes spread all over the web more than one way to handle the absurd compute load.

https://en.wikipedia.org/wiki/Worldwide_LHC_Computing_Grid
 
You also need to make sure the cable is level, otherwise one branch gets more signal voltage than the other...

Jan

Jan

You are mixing up voltage and current again. Everyone knows the currents are much stronger at a sharp drop. Sometimes you get splashed at electron falls. Very pretty to look at but the spray of stray electrons can make mess for things too close. That is why some folks put their loudspeaker cable up on blocks. It has nothing to do with reducing capacitance or non uniform solenoid effect.

There was a high school teacher who used to be a stickler about the difference. I think he may even have written a paper. His name was Georg Simon Ohm. Interestingly enough he sort of looked like the actor Simon Baker. (Mentalist TV show.)
 
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Wahab; Really? I thought it was pretty good at ANY level. The instrument bottoms out at -140... the monitor output into FFT (QA401) has to be used to tell how much lower than -140 it really is. Oh well. Back to the drawing board, I guess. You guys are hard to please.

:)
THx-RNMarsh

Ok, i thought that it was displaying an actual measurement of 0.1ppm THD...

Other than this i like linearity for the fun of the challenge, otherwise i m perfectly happy using amps that barely do better than 0.02% distorsions.


I've got a Y cable. Needs traffic lights for the electrons....


Electrons speed is 0.02mm/s IIRC, that is to say that with AC currents they are not moving at all on average..
 
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Ok, i thought that it was displaying an actual measurement of 0.1ppm THD...

Other than this i like linearity for the fun of the challenge, otherwise i m perfectly happy using amps that barely do better than 0.02% distorsions.

yes, it is an actual measurement.... i didnt go into the unit and force the readout display to show -140db. There is shown a cable connected to the analyzer input and it is in THD measure mode. 30Khz LPF only. [btw, with this instrument, when signal level is too low -less than 0.5 v rms - the display is blank/blacked out]

Yes, it is fun. And, it IS still just a hobby sport in support role for the music. Not to be taken very seriously. No one's life depends on it.


THx-RNMarsh
 
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