Tangent: Interest Check: Belden Thicknet 10base5 Ethernet Coax
paulkoning at comcast.net
Fri Feb 2 18:54:38 CST 2018
> On Feb 2, 2018, at 7:26 PM, Paul Berger via cctalk <cctalk at classiccmp.org> wrote:
> On 2018-02-02 7:13 PM, Fred Cisin via cctalk wrote:
>>> they might have different ground systems. If so, grounding both ends might produce a LARGE current through the cable, possibly enough to be hazardous.
>> OB_Ignorant_Question: Is that the reason why RS232 DB25 has both pin 1 and pin 7?
> Pin 1 is supposed to be protective (shield) ground and pin 7 is signal ground.
Similar to safety ground (green) and neutral (white, in the USA) on power wiring.
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