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Re: Basic Electricity

Subject: Re: Basic Electricity
From: Walter Knapp <>
Date: Sun, 16 Jan 2005 12:34:33 -0500
From: "Rich Peet" <>

> 
> 
> I have read the stuff they wrote, but for the configuration of inner 
> wires to matter that means that the shield already has failed and 
> what you needed was a better shield. And so, I don't buy into their 
> sales stuff on reverse twisting.

This is all wet, no amount of copper stops magnetic fields, which pass 
right through the cable. And the configuration of the wires is designed 
to deal with the alternating electromagnetic field's induced voltage in 
the wires of the cable. Electromagnetic fields also are induced in the 
shield for that matter, those do get grounded out and are not connected 
to the signal conduction if it's really a balanced system.

The braid shield is only good at electrostatic fields. And at least the 
Canare cable has a excellent braid shield. It is far from a failure, it 
does all that a copper based shield could do.

It's not a matter of sales, star quad was developed by the engineers at 
the BBC just for it's ability to resist electromagnetic interference 
from all the cables that are found in a TV studio. A number of designs 
were tested, star quad came out best. Canare just made their design into 
a commercially available cable.

I believe that Canare invented the name star quad.

> The big reason why the star quad cable is worth the extra money is 
> how flexible it is in cold temps.  For field use outside in the cold 
> I know of no better. I like the low profile.

It is premium cable, and that does include it's handling characteristics 
which are very good, but not unique. For nature recording that's a 
important factor, maybe more important than it's electrical 
characteristics, because we normally record far from sources of 
electromagnetic radiation, but for studio work the electrical 
characteristics are most important. And are the reason why most of the 
users of the cable buy it.

I first went to it for it's electrical characteristics. It was a bonus 
that it's handling was so good. Not the other way around.

Walt





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