[time-nuts] Standards sought for immunity of shielded cable links to power-frequency ground loops

[Poul-Henning Kamp]

In message <OFADE54B4F.D29DBA7A-ON85257537.00086866-85257537.000907CA at mck.us.ra
y.com>, Joseph M Gwinn writes:

>The effect of differing ground potentials on a shielded cable is to pull a 
>large current through the shield, [...]

The correct enginering solution is to use twinax, ground the shield
in one end only and transformer-couple the signal at least in the
other end from the grounding.

Look at IBM's 5250 terminal hookup for an school book example of getting
it right.

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