[sdiy] Lego synth anyone?

[James Patchell]

I should not have used the term "noise gain" below...oh well, typing too 
fast...

At 09:04 AM 1/17/2005 -0800, James Patchell wrote:
>No, this is a real effect.  First of all, two uncorrelated noise sources 
>do not add.  What you get is the square root of the sum of the 
>squares.  So, if you have two noise sources that put out 1 VRMS, the "sum" 
>would be the square root of 2 (1.414).  Two signal sources, of course, add 
>up algebraically.  So, the more transistors you connect together, the 
>signal gain increases at a faster rate than the noise gain.
>
>For a reference, locate a copy of "Low Noise Electronic Design" by 
>Motchenbacher and Fitchen, page 249....
>
>At 01:02 PM 1/17/2005 +0100, synthos at xs4all.nl wrote:
>
>> > Paralleling transistors can lower noise as the signal is in phase, while
>> > the noise is random and 'should' cancel out. A few transistors produces a
>> > benefit...
>>
>>Is that a fact? Do you perceive it like that?
>>If you add two noise sources, they add up. Being random, there
>>is no such thing as cancelling out.
>>
>>Or, is this why resistors come in matched pairs ;-)
>>(I like those 'three in a package' no-noise resistors!)
>>
>>
>>Dave Krooshof
>>
>>Dendriet
>>
>>
>>
>>
>>
>>
>>
>> > H^) harry
>> >
>> > anthony wrote:
>> >
>> >> > In his BBD based delay module, Thomas Henry parallels some inverters
>> >> for
>> >> > increased drive. What are you trying to achive.
>> >>
>
>         -Jim
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>http://www.oldcrows.net/~patchell
>
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>

         -Jim
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http://www.oldcrows.net/~patchell

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