Re: The decibel

On Wed, 22 Aug 2007 03:15:13 +0100, Eeyore
<rabbitsfriendsandrelations@xxxxxxxxxxx> wrote:

Do you think it is higher or lower than 600 ohms?

I was under the impression it could be lower but I see the standards still refer
to 600 ohms.

The characteristic impedance of the twisted pair cable is actually around 100
ohms and DSL circuits operate at this impedance. So it's 600 ohms for audio and
100 ohms for data.

The big numbers are for open-wire line with huge (by modern standards)
spacing. Modern plastic-insulated twisted pairs tend to fall, as
you say, around 100 ohms.

And the World is 72 ohms. The Wires have almost got it right.

Thanks, as always,

Chris Hornbeck
"It's just this little Chromium Switch.
You people are SO superstitious."
.

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