BL> ... HINT: why doesn't line 2 have some B and Line 1 some C?
 RM> Is this relevant in some way? Doing that doesn't alter the
 RM> original problem at all. Or am I missing something that you
 RM> learned in your recent NDE?
 BL> No... NDE is not necessary. It's something I learned in 40
 BL> years as an electronics engineer, something you seem to have
 BL> missed,
 RM> WHAT, exactly? I still don't get it.

  ROFL!

 BL> you'll perhaps see that your arithmetic really has nothing to
 BL> do with what Chris has in mind.

 RM> As far as I can see, a set of simple equations explains the
 RM> problem more concisely and clearly than any amount of blather.
 RM> I still don't get you. Please elaborate.

  Ask Chris. He now understands.

  If you stand a singer between two stereo microphones onstage, the
singer-signal at each microphone is almost the same in phase and
amplitide, and if you feed both into a differential amplifier they
cancel and the singer disappears. What Chris suggested was the
reversal of this, using a common-mode amplifier rather than a
differential amplifier! ROFL!

  This is plain silly. It's a howler! It the sort of thing a raw
beginner suggests. It sort-of makes sense if you don't think about
it... and you didn't think! It sort-of seems that common-mode is the
opposite of differential. What he wants is an amplifer that cancels
everything that isn't the same! ROFL!! You compare two signals and if
they're not the same they cancel! Just invert one side? ROFL!!

  I led Chris gently towards realisation but when you came on with
your pedantic "basic theory" explanation I could not resist twitting
you. But I don't want to think about it from your point of view. It 
makes my head hurt. I keep thinking an amplifer that cancels everything 
that wasn't the same would eat the World.

Regards,
Bob
___ Blue Wave/QWK v2.12
@EOT:

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