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Re: Basic Electricity

Subject: Re: Basic Electricity
From: "Rich Peet" <>
Date: Thu, 20 Jan 2005 21:02:46 -0000
I made certain early on when I was asked through a contact from this
list that MOU would be represented.  I did get in my dues finally as a
note on the side. Jerry Bonkowski is to be there tommorrow.

I hope that they put me next to him.  I have not figured out how many
dishes would be to many to manage of these big things but think maybe 5.

Rich

--- In  "Alt, Mark" <>
wrote:
> I would like very much if you would consider doing this presentation as
> part of the MOU Youth Mentorship Program. We track who we present to and
> there is money available to build kits for such presentations.
>
> Mark Alt
> MOU President
> 
> C/O J. F. Bell Museum of Natural History
> University of Minnesota
> 10 Church Street SE
> Minneapolis, MN 55455-0104
> MOU.mn.org
>
>
>
> -----Original Message-----
> From: Rich Peet 
> Sent: Thursday, January 20, 2005 2:19 PM
> To: 
> Subject: [Nature Recordists] Re: Basic Electricity
>
>
>
> Clearly I am having trouble understanding and belief of why star would
> have a ten fold reduction or 20db over an equiv. shielded 2 wire.  And
> I appreciate your attempt as well as Walts in explaining it to me.
>
> In further thought it makes no sense for me to buy the 2 wire version
> when I like the 4 wire because of possible breaks, and maybe even the
> "magic" that accounts for a noise reduction.
>
> Right now I am preparing a parabolic presentation for a large group of
> K to 12 science students.  I am sure they all will have fun and
> education with a group of 32" dishes and Randys math for a hands on
> learning experience.
>
> Rich
>
> --- In  "kennjava" <> wrote:
> >
> > --- In  "Rich Peet" <>
> > wrote:
> > >
> > > --- In  "kennjava" <>
> wrote:
> > > >
> > > > The 4 conductors in the twisted "star" pattern provides more
> physical
> > > > symmetry of the signal-carrying conductors; this symmetry means
> that
> > > > signals induced along the cable are more completely cancelled
> out by a
> > > > differential input.
> > >
> > > Of course you understand that there would be much more symmetry if
> > > there was only two wires running directly next to each other.
> > >
> >
> > I don't see how that could be so... (otherwise normal mic cable would
> > be less prone to noise than star-quad, right?)
> >
> > If you consider a pair in cross-section (A and B) and noise source (N)
> > like so:
> >
> > 1)               AB          N
> >
> > 2)               A           N=20
> > 2)               B
> >
> >
> > Then in 2) A and B are receiving the same signal from N, but in 1) B
> > is closer therefore recieving more signal from N.
> >
> > Isn't that the whole point of pair twist - so that over a length of
> > cable the distance  A to N and B to N average out to be equal... which
> > means equal amounts of induced noise, which means better cancellation.
> >
> > And star-quad improves upon that, because it's cross-section is never
> > as asymetrical as 1).
>
>
>
>
>
>
> "Microphones are not ears,
> Loudspeakers are not birds,
> A listening room is not nature."
> Klas Strandberg
> Yahoo! Groups Links





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