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Three fingers of single-malt scotch...

Hi Larry,

Thanks for shedding light on this subject.

It didn't even take me three fingers of scotch to figure out
the benefits of using the "unused pairs".... but, in the future
I may refer to the benefits of using something that is freely
available and capable of providing extra margin the "three finger
rule" if you don't mind.



Dan Dove
HP ProCurve Networks

>  -----Original Message-----
>  From: Larry Miller [mailto:ldmiller@xxxxxxxxxxxxxxxxxx]
>  He could hardly believe it. Could this FREE isolation be 
>  real? There was
>  only one way to find out-- hook up some cables on the trusty network
>  analyzer and see if it panned out.
>  The figures did not lie. In fact, the cable sample used was 
>  even BETTER
>  than the advertised numbers. 
>  Even with the crummy NEXT of RJ-45 connectors, the isolation 
>  below 30 MHz
>  was at least 15 dB (5.623:1) under the worst case conditions he could
>  produce by wiggling cables. And these were REALLY bad cables.
>  Awe-struck by this Truth, Larry thought, "Clearly, this is 
>  not an advantage
>  to be lightly disposed of by attaching power supply parts 
>  directly to the
>  signal wires! No indeed! Not when you can reduce the risk of 
>  interaction by
>  nearly an order of magnitude by simply using those wires 
>  that hadn't been
>  used previously!"
>  It seemed almost a Meeting with Destiny, seeing a terrific 
>  use for these
>  previously neglected, so-called "unused" pairs of wires.
>  Larry shuffled off, rather shaken by this experience. 
>  Clearly, this was
>  going to take some consideration and quite possibly about 
>  three fingers of
>  single-malt Scotch to fully absorb it all...."
>  (End of Quote, with due apologies to Douglas Adams)
>  No, Roger, this is not about politics. Ya picked the HARD 
>  set of wires to
>  use, ole buddy!
>  Regards & no offense,
>  Larry