Quite some time ago, for the purpose of determining the effect of ground on the
terminal impedance of a dipole, I measured the terminal impedance of a
center-fed dipole, length 32.33 ft. at frequencies every 50 KHz from 14.0 to
15.0 MHz, at heights of 0, 1, 2, 3, 4, 5, 8, 10, 12, 14, 16, and 22 ft above
ground. A total of 252 individual measurements.

The equipment used for the measurements were a calibrated 40 ft RG-58 feedline,
[calibrated for electrical length and attenuation at frequencies f(x)], a balun
consisting of 100 #73 beads over a 2 ft length of RG-303 coax (included in the
feedline calibration), a General Radio GR-1606-A RF impedance bridge, a Ferris
Microvolter 70B signal generator, and a Collins 75A-4 receiver.

The input impedances appearing at the input of the feedline were then
transformed using the W2DU software program 'LINTRNSA' to obtain the impedances
appearing at the dipole terminals. (LINTRNSA appears in both the 1st and 2nd
editions of Reflections.)

The total data includes the R and X components of the impedances appearing at
the input of the feedline, the values of rho and swr at both the feedline input
and at the dipole terminals, and the R and X components of the dipole terminal
impedances. A total of 2016 data points.

All of the data listed above is in tabular form, ready for putting into a PDF
file for use by anyone who is interested in reviewing the data. The data is
presented in the same format as in Reflections, Tables 15-4, 15-5, 20-1, 20-2,
etc.

If anyone is interested I'll make the PDF file, and I'll be pleased to send it
to all who would like a copy. Just give me a jingle (via email, that is at
.

Walt

Walt, did you measure ground conductivity and permittivity?

Or did you forget like messrs B, L & E.
----
Reg.

"Reg Edwards" wrote in message
...
Walt, did you measure ground conductivity and permittivity?

Or did you forget like messrs B, L & E.
----
Reg.

No, Reg, I had no way of measuring them at the time. I was hoping to be able to
interpolate the measured data in some way to determine conductivity and
permittivity.

Walt

On Sun, 19 Jun 2005 14:27:37 -0400, "Walter Maxwell"
wrote:

No, Reg, I had no way of measuring them at the time. I was hoping to be able to
interpolate the measured data in some way to determine conductivity and
permittivity.

Hi Walt,

Your interpolation is by far and away going to be superior to ANY
method Reg has to - well, I was going to say offer - but, Reg, you
have never had any method to offer, have you? You have sort of
mumbled on about mud in the kitchen sink, and averred to secret
recipes, but your limited experience with English garden soil is
rather inconsequential.

Walt, put me on your distribution list for those results. My copy of
your book is in other's hands.

73's
Richard Clark, KB7QHC

"Reg Edwards" wrote in message
...
Walt, did you measure ground conductivity and permittivity?

Or did you forget like messrs B, L & E.
----
Reg.

Hi Reg, it appears you have a copy of the B, L & E's IRE paper reporting their
ground radial experiments, "Ground Systems as a Factor in Antenna Efficiency,"
that the FCC finalized on in the radial requirements for AM BC stations. Their
paper was dated June 1937. I knew B (George H. Brown) very well, as he was
formerly the chief engineer of the antenna lab of the RCA Laboratories. I also
knew L, (Bob Lewis, W2EBS) as well, but only as a ham, because he left the RCA
Labs before I worked there. I worked alongside E, (Jess Epstein) for many years
at the Labs.

Jess told me why their experiments included 113 radials. It seems that when Jess
had plowed in 100 radials he asked Brown what he should do with the wire
remaining in the spool. Brown said, "plow it in." There was just enough wire
left for thirteen more radials--hence the 113, as reported in their IRE paper.

I attended a radio club meeting where Bob Lewis was a member on a night when
Jerry Sevick, W2FMI, was the guest speaker. Jerry was explaining how radials
worked. In his blackboard diagram he included concentric wires connected to each
radial at various intervals away from the vertical radiator, including at the
ends of each radial. I asked Jerry what those concentric wires were for, but he
had no answer. Bob Lewis was in his audience, so I then asked Jerry if he knew
about the Brown, Lewis & Epstein experiment concerning ground radials. Jerry
said, yes, he did. I then asked him if he'd like to meet Bob. He said he
certainly would when the time was right. So I told Jerry the time was right
right now, and asked Bob to stand. Bob then took the stage, and much to Jerry's
chagrin, Bob told the group how radials really worked.

At the end of the meeting a photographer took a picture of Bob, Jerry, and me,
that was published in QST sometime in the 60s or 70s, I've forgotten just which
issue.

Walt, W2DU

hi Walt, I'd like a copy of your measurements..73 Leon W5GY

Walter Maxwell wrote:
Quite some time ago, for the purpose of determining the effect of ground on the
terminal impedance of a dipole, I measured the terminal impedance of a
center-fed dipole, length 32.33 ft. at frequencies every 50 KHz from 14.0 to
15.0 MHz, at heights of 0, 1, 2, 3, 4, 5, 8, 10, 12, 14, 16, and 22 ft above
ground. A total of 252 individual measurements.

The equipment used for the measurements were a calibrated 40 ft RG-58 feedline,
[calibrated for electrical length and attenuation at frequencies f(x)], a balun
consisting of 100 #73 beads over a 2 ft length of RG-303 coax (included in the
feedline calibration), a General Radio GR-1606-A RF impedance bridge, a Ferris
Microvolter 70B signal generator, and a Collins 75A-4 receiver.

The input impedances appearing at the input of the feedline were then
transformed using the W2DU software program 'LINTRNSA' to obtain the impedances
appearing at the dipole terminals. (LINTRNSA appears in both the 1st and 2nd
editions of Reflections.)

The total data includes the R and X components of the impedances appearing at
the input of the feedline, the values of rho and swr at both the feedline input
and at the dipole terminals, and the R and X components of the dipole terminal
impedances. A total of 2016 data points.

All of the data listed above is in tabular form, ready for putting into a PDF
file for use by anyone who is interested in reviewing the data. The data is
presented in the same format as in Reflections, Tables 15-4, 15-5, 20-1, 20-2,
etc.

If anyone is interested I'll make the PDF file, and I'll be pleased to send it
to all who would like a copy. Just give me a jingle (via email, that is at
.

Walt