Art wrote:
"I have determined that coupling of elements which means parasitic
elements is wasteful."

A parasitic element is normally constructed of low-loss material and
re-radiates all the energy it absorbs from the radio wave. If it is
placed and phased right it can reinforce radiation in the desired
direction.

Kraus in the 3rd edition of "Antennas" has his close-spaced all-driven
W8JK array and a wide-spaced all-driven 2-dipole array in the same
figure, Fig. 6-12, on page 184. The gain of either antenna is about 6
dB, supposedly with respect to an isotropic, or about 4 dB with respect
to a dipole. Both arrays are bidirectional.

Arnold Bailey catalogs a version of the W8JK close-spaced all-driven
array on page 511 of "TV and Other Receiving Antennas". On page 516 is a
1/2-wave radiator with a 1/2-wave parasitic reflector 1/4-wave behind it
(a simple Yagi).

Bailey gives the W8JK a resistance of 7 ohms and a gain of 4 dBd (6
dBi).

Bailey gives the parasitic array a resistance of 28 ohms and a gain of 5
dBd 7dBi). The parasitic array is slightly unidirectional while the
pattern of the W8JK is symmetrical.

Best regards, Richard Harrison, KB5WZI

Richard Harrison wrote:

...
A parasitic element is normally constructed of low-loss material and
re-radiates all the energy it absorbs from the radio wave.
...

Although this is nit-picking, the above is impossible, some percentage
of rf MUST be lost as heat (poor joints in elements/booms can GREATLY
enhance loss also) ...

The rest of your text seems to be generally accepted ...

Regards,
JS

On 26 Apr, 09:37, (Richard Harrison) wrote:
Art wrote:

"I have determined that coupling of elements which means parasitic
elements is wasteful."

A parasitic element is normally constructed of low-loss material and
re-radiates all the energy it absorbs from the radio wave. If it is
placed and phased right it can reinforce radiation in the desired
direction.

Kraus in the 3rd edition of "Antennas" has his close-spaced all-driven
W8JK array and a wide-spaced all-driven 2-dipole array in the same
figure, Fig. 6-12, on page 184. The gain of either antenna is about 6
dB, supposedly with respect to an isotropic, or about 4 dB with respect
to a dipole. Both arrays are bidirectional.

Arnold Bailey catalogs a version of the W8JK close-spaced all-driven
array on page 511 of "TV and Other Receiving Antennas". On page 516 is a
1/2-wave radiator with a 1/2-wave parasitic reflector 1/4-wave behind it
(a simple Yagi).

Bailey gives the W8JK a resistance of 7 ohms and a gain of 4 dBd (6
dBi).

Bailey gives the parasitic array a resistance of 28 ohms and a gain of 5
dBd 7dBi). The parasitic array is slightly unidirectional while the
pattern of the W8JK is symmetrical.

Best regards, Richard Harrison, KB5WZI

I did a quick scan of your response and only see book references so I
suppose that is the end of that since I also have books of my own.
Art

Richard Harrison wrote:


Bailey gives the W8JK a resistance of 7 ohms and a gain of 4 dBd (6
dBi).


I've always wondered how he managed to have "NO SIGNAL RESPONSE IN THIS
PLANE" for yz though. He must have built and balanced things really
well.

tom
K0TAR

Tom Ring, K0TAR wrote: "I`ve always wondered how he managed to have "NO
SIGNAL RESPONSE IN THIS PLANE" for yz though. "

I guessed that Arnold Bailey just assumed perfection in some instances
for practical purposes. My own experience has been that differences of
less than one dB were not to be confided in. Reg Edwards used to speak
of "delusions of accuracy", and I think he grasped a lot of wisdom
there.

Best regards, Richard Harrison, KB5WZI

Richard Harrison wrote:

I guessed that Arnold Bailey just assumed perfection in some instances
for practical purposes. My own experience has been that differences of
less than one dB were not to be confided in. Reg Edwards used to speak
of "delusions of accuracy", and I think he grasped a lot of wisdom
there.

Best regards, Richard Harrison, KB5WZI


I was being a bit facetious, Richard. I couldn't resist after looking
at the page, and knowing that there really could not have been "no
response".

tom
K0TAR