TECH: PAR Electronics Omniangle OA-50 (6 Meters)

[WB7X]

With the upcoming CQWW VHF QSO Party coming up this weekend (7/16/2011), and the recent 6M band openings, I thought it might be a good time to upgrade my 6M antenna. Currently I have been using the Icom 7000/AH-4 with about a 65’ long wire at 5’. While that setup produced results on 6M, I wanted to get more antenna without going to a yagi/rotor.

Researching the WWW, I found PAR Electronics and their Omniangle series of horizontal “loop” antennas. An email to the company got a quick and courteous response from the owner Dale Parfitt W4OP. Dale’s company manufactures a myriad of products right here in the USA, including the Omniangles and a 6M Stressed Moxon.

I ordered the OA-50 late in the day on 7/6/2011, had a tracking number the next morning, with the antenna arriving on 7/13/2011. Dale had even emailed to confirm that I got my tracking number as I was one of a bunch of orders that wanted delivery before the CQWW event. Great customer service!

Now to the OA-50. The antenna is a triangular shape that is slightly more than a ½ wavelength. PAR states that this design is as close to a perfect omni as possible, and more so than other square or round “loop” type antennas.
Power handling rating is 160 watts. Weight is 1.5 pounds.

The radiator is made of ¾” square aluminum tubing with a hole drilled in each end to accept the 5/16” tubes. The holes are drilled with such tolerance that the when the tubes are inserted and curved via the shrouded tip assembly, the friction created allow no movement. The tubes are 5/16” round aluminum tubing. The shrouded tip assembly consists of aluminum inserts inside of a PVC type tube. The ends of this assembly slide into the free ends of the 5/16” tubing.

The manual states that the 5/16” tubes are inserted through the radiator 1”. SWR adjustment is accomplished my manually slightly straightening the tubes to relieve the friction and sliding them in or out to adjust SWR. (Pretty slick).

For base operation, a “nail” is provided with the antenna so that you can “stake” the shrouded tip assembly to the tubes. For mobile/portable operation, you may not want to do that in order to have quick dis-assembly.

Assembly is very easy and was done in about 10 minutes with minimal tools.

The OA-50 as removed from the well packed shipping box. Square tubing sections are pre-assembled. The small black box is a balun and is ready to attach via the two screws that also attach the mounting brackets/insulator to the radiator. (As the radiator is insulated from the support mast, a metal mast can be used).

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A better view of the contents:

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A close up view of the mounting bracket/insulator and balun:

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Mounting bracket/insulator and balun assembled to radiator:

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Antenna during assembly:

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Close up of the apex spacer:

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Assembled OA-50:

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OA-50 shown with it’s little brother OA-144 (2M)

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(Note: The apparent “bending” of the radiator is a camera anomaly)

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Installed on the portable mast: Ultimately it will be on the roof mast below the Cushcraft AR-270B 2M/70CM collinear vertical.

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Tested: I made a minor adjustment to 1 ¼” tubes showing through the radiator.

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It is easy to see why Eham reviewers rate this antenna a 5/5. It looks like it would make a fine base/portable antenna and some even run them mobile.

Price for the OA-50 currently is $99 plus $12 shipping. Orders may be placed through the website. Further information is available at the PAR Electronics website http://www.parelectronics.com/index.php

Photo Credit to my YL WD7DX. Copyright www.WB7X.net

Disclaimer: Opinions are my own. I paid retail for the OA-50 and have no financial or other interests in PAR Electronics or Icom.

[K7VZ]

Marty, that looks magical. Good writeup. What is the isolator made of? It looks like some sort of plastic block?

[WB7X]

Fiberglass angle for the mount. Looks like a plastic/delrin type material for the square insulator between the radiator halves. No idea what's inside the "balun" as it's sealed. I've been working a bunch of 6 lately. Still don't have it up on the roof yet. PAR also makes a 6M moxon that looks interesting, but would require a rotor if used as a base. The moxon is 5.5 db gain, while stacked omniangles would be 3, but wouldn't need to rotate. Dale seems like a nice guy. I sent him a link to the review and he checked out this site and left a rating. :)

[K7NNT]

Looks like a well made antenna!