Here you are, paying attention to the man behind the curtain. I thought
you weren't supposed to do that.

Roy Lewallen, W7EL

Richard Clark wrote:
Well, I did mention in another thread that Cecil had already passed
the milepost indicating the point of no return:

On Tue, 04 Dec 2007 19:16:01 GMT, Cecil Moore
wrote:
I also measured ~12-13 ns delay
through 50 turns of the same coil stock that Tom
was using when he measured a 3 ns delay through
a 100 turn coil.

The "results" (not corrected for errors as all of Cecil's arguments
drawn from reality are cast as perfections - a clash that always
amuses me) at this point Cecil confirmed/validated Tom's screen shot.

How? Tom's instrument is built to compensate for two channel
measurement errors, an ordinary scope is not. There are many issues
to resolve when using an ordinary scope before results (then corrected
for error) can be used in comparison.

Why? The error is an inherent disparity in using two channels, and
their different rise times. It shouldn't take a degree in engineering
(many who own scopes can confirm this) to realize that an identical
event, traveling through the parallel chain of amplifiers eventually
driving the deflection of the parallel traces; each of those in the
pair will arrive at a different time.

What? It only remains to resolve which chain presents more (or less)
rise time. It is not uncommon to find in the extreme (exactly where
Cecil's measurement resides) that rise time differentials can easily
equal the time delay measurement cited above in the quote, but for
Leader O'Scopes, a calibrated model can exhibit up to 17.5nS rise
time.

Remove that differential, and the error corrected delay collapses
towards Tom's results! If we consider the span of all error easily
washes over the resolution of the measurement, then Cecil's particular
test was a non-starter as it is arguable that it was ever performed.

Cecil could yet pull some of this error out of the mud, but his memory
is foggy, he can't find things, problems beset him, poor eyesight may
have disturbed what he reported (transcription error), his
instrumentation isn't calibrated, he even admits to the possibility of
spelling errors (communication failures in this forum seem to be
embraced as a mark of populist heroism in the face of sterile
engineering), and on and on until:

SUDDENLY a new fact arises that completely
vindicates Cecil! A new vigor rises, and there are
more than 20 answers to supply!
Memory suddenly clears,
the lost notebooks are found,
problems vanish,
eyesight is restored to 20/20....
well, let's say that drama takes center stage
as the magician's cape opening reveals the rabbit.

There are other errors to answer for, this one was simply the first to
engage Cecil in his stumbling attempt cursing the pebbles in the path
as boulders. The absolute best outcome Cecil could reasonably expect
to show is the standard RL of an ordinary coil, and Corum would have
to wait for a future validation. Of course, this future occasion
would demand far better controls, tighter readings, better reporting;
and, of course, this verges on the dictates of engineering.

The cursing will, no doubt, follow. :-)

73's
Richard Clark, KB7QHC