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[NU8L]

I have a 2 element Cubical Quad.  I wish to add 2 additional elements and make a 4 element quad.  The quad is a 10 to 20 m tribander.  I am using a HAM IV rotator.  Will the HAM IV be enough rotator?  The elements are 1.5 inch O.D. and 13 feet long.  The boom is 4 inch heavy wall aluminum irrigation pipe.  The boom is 30 feet in length. Does anyone have the info to calculate wind load of round elements?  Does anyone have experience with 4 element quads? --- NU8L

[K0SR]

I've been turning multi-element Quads with my venerable old Ham IV for about 25 years now.  My current antenna has 3 elements on 20, 17 and 15 metes, and 4 elements on 10 and 12.  This is on an eighteen foot boom.  A 30 foot boom is going to present a lot more torque.  The brake will probably hold, but it may not spin right away on a windy day.

Years ago there was an excellent article in Ham Radio magazine on calculating wind loads.  I have a copy of it, I'd be happy to make another copy of it and send it to you if you'd be interested.

73 Steve K0SR

[NU8L]

Thanks Steve, K0SR.

Yes, I would be very interested in the Ham Radio article.  My Mailing address is 4189 48 Road West, Cadillac, MI. 49601.  

I have all the parts to build this upgrade but I am not sure what the rotator requirements will be.  I have not found much in the literature about surface area and wind loads of antennas.  Oddly enough, the ARRL handbook is lacking also!

Regards, Alton

[K0SR]

OK, I'll have it in the mail tomorrow.

Steve K0SR