-----Original Message-----
From: Peter Chadwick <Peter.Chadwick@zarlink.com>
To: Ian White, G3SEK <G3SEK@ifwtech.co.uk>; amps@contesting.com
<amps@contesting.com>; 'G8GSQ' <g8gsq@qsl.net>
To: <amps@contesting.com>
Date: 05 April 2002 07:46
Subject: RE: [Amps] Re: [Amps] Re: [Amps] Re: [Amps] Re: [Amps] BirdR 43
Manual
>Steve said:
>
>>Doesn't the 'usual' construction use a coax throught the current
transformer,
>>with one end of the outer disconnected so you get the continuity of
>>transmission line impedance while also getting the current transformer
>>effect.
>
>If the outer is disconnected, there's no current flow in it, so how does it
>maintain
>the impedance? I believe that you use the coax to provide electrostatic
>shielding to prevent capacitive pick up.
It certainly does the latter. I'd always assumed (without doing any sums)
that the inner-outer capacitance still worked with the inner's inductance to
minimise impedance discontinuity compared with just a bare wire.
Steve
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