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Old August 7th 06, 04:29 PM posted to rec.radio.amateur.antenna
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Default Homemade 440 yagi question

I built a 6 element 432mhz yagi from instructions in the ARRL Handbook. I
used a 1" wood dowel for the beam and 1/4" aluminum rod for the elements. I
used a "T" match on the driven element. One on each side, just like the
illustrations show. And a 1/2 wavelength phasing line.

But the instructions don't show or say if the driven element is split in the
middle.

Shouldn't the driven element be split.


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Old August 7th 06, 04:57 PM posted to rec.radio.amateur.antenna
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Default Homemade 440 yagi question

"Bart" wrote in
:

I built a 6 element 432mhz yagi from instructions in the ARRL
Handbook. I used a 1" wood dowel for the beam and 1/4" aluminum rod
for the elements. I used a "T" match on the driven element. One on
each side, just like the illustrations show. And a 1/2 wavelength
phasing line.

But the instructions don't show or say if the driven element is split
in the middle.

Shouldn't the driven element be split.


The short answer is no.

The T-match produces a current through that portion.



--
Dave Oldridge+
ICQ 1800667
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Old August 7th 06, 06:02 PM posted to rec.radio.amateur.antenna
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Default Homemade 440 yagi question

Think of the "T" match (with the driven element) as being similar to a
folded dipole. The element should not have a break in the middle, just
as the second wire in the folded dipole should not. If you put a break
in the middle, it would become for all practical purposes just a
center-driven dipole.

Cheers,
Tom


Bart wrote:
I built a 6 element 432mhz yagi from instructions in the ARRL Handbook. I
used a 1" wood dowel for the beam and 1/4" aluminum rod for the elements. I
used a "T" match on the driven element. One on each side, just like the
illustrations show. And a 1/2 wavelength phasing line.

But the instructions don't show or say if the driven element is split in the
middle.

Shouldn't the driven element be split.


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Old August 7th 06, 09:49 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jul 2006
Posts: 444
Default Homemade 440 yagi question

Bart wrote:

I built a 6 element 432mhz yagi from instructions in the ARRL Handbook. I
used a 1" wood dowel for the beam and 1/4" aluminum rod for the elements. I
used a "T" match on the driven element. One on each side, just like the
illustrations show. And a 1/2 wavelength phasing line.

But the instructions don't show or say if the driven element is split in the
middle.

Shouldn't the driven element be split.



NOT with a Tee match!

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Old August 8th 06, 12:23 PM posted to rec.radio.amateur.antenna
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Posts: 162
Default Homemade 440 yagi question

No, the driven element can be one solid piece...you just connect the
shields of the "phasing line" to the driven element right where they
exit on each side of the boom. The centers of the phasing line connect
to each side of the T match where they come out of the boom. The T
match sections ARE split. That's how I did my 222 yagi that I took out
of the ARRL antenna book (the old NBS designs).

Scott
N0EDV

Bart wrote:

I built a 6 element 432mhz yagi from instructions in the ARRL Handbook. I
used a 1" wood dowel for the beam and 1/4" aluminum rod for the elements. I
used a "T" match on the driven element. One on each side, just like the
illustrations show. And a 1/2 wavelength phasing line.

But the instructions don't show or say if the driven element is split in the
middle.

Shouldn't the driven element be split.


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