Thread: Tocord
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Eeyore Eeyore is offline
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John Larkin wrote:

Ross Herbert wrote:
John Larkin wrote:
:"Phil Allison" wrote:
:
:Can you come up with a better way to reduce or eliminate cable inductance?
:
:I've used an easier one:
:
:Start with a hunk of the MIL-spec stranded wire, #8 or #10 maybe, the
:kind with the fine silver-plated strands and very thin-skin black
:teflon insulation.
:
:Stuff that inside a tubular woven copper braid. Pull the braid to
:tighten it around the inner conductor, then finish with shrink tubing.
:The result is homemade coax with a very thin dielectric, which
:translates to very low inductance per unit length.
:
:I've done this for driving longish (like 10 m) runs to NMR gradient
:coils, where the cable L really matters. The improvement over other
:constructions, like twisted pairs, is dramatic.

Sounds good to me.

Somewhat along these lines John?
http://www.sumikoaudio.net/ocos/idx_products.htm


No. They show a thin inner conductor with thick insulation. Impedance
goes as the log of D/d, where D is the diameter of the shield and d is
the diameter of the inner conductor. So to make D/d approach 1 (and
impedance approach zero) the insulation must be as thin as possible
(which adds capacitance, of course.)


My thinking too. That looked more like heavy duty video cable.


The impedance graphs and text on the cited web page are made-up lies.
But I suppose the wilder the lies, the more audiophools will pay.


No surprise there then.

Audio doesn't really matter anyhow.


It does to me. I like my music as perfect as possible.

Graham