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View Full Version : An open-stub J-Pole for 70cm



VU2NAN
09-04-2011, 06:21 PM
May be accessed at:

http://nandustips.blogspot.com/2011/09/open-stub-j-pole-for-70cm.html

73

Nandu.

ND5Y
09-05-2011, 01:23 PM
I made something like that once. The dimensions were a little different. It seemed to work better on 70 cm than a 1/4 wave.

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VU2NAN
09-05-2011, 02:26 PM
I made something like that once. The dimensions were a little different. It seemed to work better on 70 cm than a 1/4 wave.

7335273353

Hi OM Tom,

That's a real good (and rugged) one , with a magmount.

My version can be mounted on a mast with screws.

I have not compared its performance with a λ GP but am sure it will do better.

Many thanks.

73

Nandu.

AD7N
09-05-2011, 02:38 PM
Nice handiwork! This appears to be a commercial design with a similar concept: http://www.arrowantennas.com/osj/j-pole.html

ND5Y
09-05-2011, 03:31 PM
Yes, I stole Arrow's design. I also tried making wire/SO-239 connector type ground planes like that but they never seemed to work well on 70 cm.

VU2NAN
09-06-2011, 07:33 AM
Nice handiwork! This appears to be a commercial design with a similar concept: http://www.arrowantennas.com/osj/j-pole.html

Hi OM Tony,

The Arrow dual-band open stub J-pole is rugged and easy to mount. Feed to the longer element for 70cm / shorter element for 2m makes it unique.

Many thanks.

73

Nandu.

VU2NAN
09-06-2011, 07:39 AM
Yes, I stole Arrow's design. I also tried making wire/SO-239 connector type ground planes like that but they never seemed to work well on 70 cm.

Hi OM Tom,

My 70cm connector-type ground planes work quite okay.

http://nandustips.blogspot.com/2011/02/ground-plane-antenna-for-70-cm.html

73

Nandu.

ND5Y
09-06-2011, 02:19 PM
What I should have said was a I built a 2m ground plane with a 70cm 1/4 wave stub like the one Arrow sells.
http://www.arrowantennas.com/gp/gp146.html
I have never had a problem with a normal single band ground plane.

VU2NAN
09-07-2011, 05:18 AM
What I should have said was a I built a 2m ground plane with a 70cm 1/4 wave stub like the one Arrow sells.
http://www.arrowantennas.com/gp/gp146.html
I have never had a problem with a normal single band ground plane.

Hi OM Tom,

I had a feeling that my understanding was wrong after sending my reply!

I then thought that you must have built something like this:

http://www.eham.net/articles/7005

The Arrow dual-band ground plane design is also unique.

Many thanks.

73

Nandu.

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