Thanks Richard...however the info you present doesn't deal with the real
issue that has been raised by Reg's program: (you are adressing another area
of possible disagreement)

Do 26 radials 5 metres long perform substantially as well as 26 radials 16
metres long at 3.62 mhz with the two soil constants = 25 (in my case), with
radial wire size #14 and antenna wire size #10 (I think I used 2mm and 4mm
in my calculations.)

The issue has never been (for me) how closely does Reg's program match a 1/4
wave vertical with standard length radials. The "real" question is does
Reg's program accurately reflect the performance of vastly shorter radials
than the typical "wives' tale" (Reg's characterization) 1/4 wave length
radials.

I have always accepted that some shortening of earth based (on or under)
radials (below the assumed 1/4 w or longer as in BL&E) was acceptable. The
problem is, Reg's program allows incredible shortening, predicting high
efficiency at the same time.

I have a 1000' of wire left to put down. If Reg is right, I can put down 66
radials 5 metres long and get outstanding surface coverage. If more
"orthodox" texts are correct, then I should stick with 16 metre (approx 50')
length and then I can only put down 20 more radials than the 26 I have now.

Let's not get distracted (although your point for the 20 degree antenna
shows yet another departure from BL&E).

Here's the fundamental contradiction between Reg's program and the orthodox
approaches:

================================================
Reg says (given the values I have stated above), that 5 metre long radials
will peform (substantially) as well as 16 metre long radials, all other
things being equal. Thinking this makes my head hurt.
================================================

BL&E seems to contradict this (although I haven't found the precise
comparison I'm looking for yet).

Tom, W8JI's, measurements seem to contradict this.

NEC-4 should be able to tell us how much current is in a radial and how that
current is distributed along the length of the wire. If it disappears into
inconsequential levels within the first 5 metres, then it confirms Reg's
assertion. If it does not, i.e., it remains at substantive levels well
beyond 5 metres, then it contradicts Reg's program, and agrees with BL&E, as
well as W8JI. (I thought NEC-4 could do this problem, maybe my assumption is
completely wrong.)

================================================== ============
If NEC-4 can't do this "current along a radial" analysis (buried or on the
surface, take your pick), then we need experimental data that shows us the
same thing: how fast does the current along a radial decrease to
inconsequential levels. If it is within the first 5 metres, Reg is right. If
not, he's wrong. It's as simple as that.
================================================== =============
Why is it so hard to get this answer?

hasan, N0AN


"Richard Fry" wrote in message
...
"Reg Edwards" wrote
"Richard Fry" wrote
N. B. for/to REG EDWARDS (G4FQP): I hope that you will be
motivated to follow through on one or the other of these offers,
and that you will post a comparison of the results of your
ready-to-run, "radial_3" DOS program as compared to the
BL&E datum, for equivalent conditions.
= = =
What equivalent conditions? Where can they be found? What was the
ground resistivity and permittivity on BL&E's site?

I am not motivated to do anything except reply to your remarks.
...
Reg.
_______________

OK, I'll do it then. Attached is a plot of BL&E's numbers versus yours,
for
the conditions stated there. Ground resistivity and permittivity were
estimated using the FCC's M-3 chart to select values of R and K at the
BL&E
test site from those shown in your program.

Other parameters for radial_3 calculations were taken from the physical
and
electrical descriptions in the BL&E paper. The OD and depth of the
radials
were estimated.

You and BL&E agree fairly well for a 90 degree vertical, but not well at
all
for a 20 degree vertical.

I'll be glad to explain how I generated my plots, and even send you the
spreadsheet, if you want.

RF