Logic Analysers

[Jon Elson]

On 02/03/2017 01:35 PM, Mouse wrote:
>>> the propagation delay as the signal gets to each pin (remember a
>>> foot is about a nanosecond.  [...])
> Not really.  A foot is about a light-nanosecond, yes, but
> high-frequency signals in copper travel by skin effect, moving
> significantly more slowly - somewhere around .6c, I think it is.
>
Well, actually, it depends on the impedance.  So, 50 Ohm 
coax cable is .6 C, twisted pair differential cable is 120 
Ohms, and the propagation velocity is a little above .7 I 
think.  Wires in open space are faster, around .8 or so, but 
the signal quality may be poor.

Jon