Cecil Moore wrote:
Ian White GM3SEK wrote:
That is also the sensible way to think about loaded antennas.
Calculate it the simple way first, assuming lumped inductive loading,
and then apply corrections as necessary. As I've said before, this
simple, solid method is the one that works. It can take you straight
to a workable prototype, which can be quickly adjusted to frequency.
Countless authors have demonstrated how to do this, and anyone can
download G4FGQ's MIDLOAD program to do the same.

The point is that IT OBVIOUSLY DOESN'T WORK, Ian, for
the delay through a loading coil. If it worked, W8JI
would not have gotten a 3 ns delay through a 2" dia,
100 TPI, 10" long loading coil. If his test setup
looked like mine, he would have measured a valid
delay around 25 ns.

http://www.w5dxp.com/coiltest.gif

Ian, are you afraid to run that test for yourself?

Cecil insists that simple routine reality tests are a "diversion".

Please don't twist my words. I insist that simple routine
*UNreality* tests are a diversion. But, my personal opinion
doesn't change anything. The model that I am using works. The
model that W8JI is using doesn't work.

Please take a look at: http://www.w5dxp.com/coil512.ez
and tell me why EZNEC disagrees with W8JI's model.

Cecil,

I believe you said you saw about a 7% shift between the two inputs to
your scope. If the 75 meter frequency was 4 MHz that shift would
correspond to a time delay of 17.5 ns. Not 3 ns, but not 25 ns either.
Is that just an estimate based on rounding to the nearest 25 ns?

This entire issue has become one of counting angels on pinheads, at
least from a numerical view. One angel more or less really doesn't matter.

73,
Gene
W4SZ