Hi Gary, It's always great to hear from you! Chris suggested checking the library and I found out that the USU research library has it (the rest of the library system up here is a joke). I found some info about a new AlfaSPID az/el rotator that might do the trick. I hope you'll be able to make it to the OAS meeting tonight so I run some info by you. Thanks again & clear skies, Dale.
-----Original Message----- From: utah-astronomy-bounces+dale.hooper=sdl.usu.edu@mailman.xmission.com [mailto:utah-astronomy- bounces+dale.hooper=sdl.usu.edu@mailman.xmission.com] On Behalf Of Gary Liptrot Sent: Thursday, September 08, 2005 5:21 PM To: Utah Astronomy Subject: Re: [Utah-astronomy] Sept. QST source for RT upgrade help
Hi Dale, I have the September QST sitting right here. The article is a product review called "A Look at a New Generation of Antenna Rotators." The author concentrates on MEDIUM duty rotators some of which I know have been around for a while. They are single axis only but some can be computer controlled quite nicely. They review the following rotators: AlfaSpid C.A.T.S. RD-1800 Hy-Gain Ham-V Prosistel PST-641D Yaesu G-800DXA (I have the G-1000SDX on a 46 foot tower)
I know that the special satellite tracking rotators (not mentioned in the article) are two axis and computer controlled. I don't know what the wind-loading specs are compared to the others in the article. Look up Yaesu's satellite rotators to find out their specs. They would be the best if they will handle the weight. Even if you just get one axis I imagine that you would have to build a small beefy mount with a couple of thrust bearings around the pipe that runs to your dish. Not hard to do. What do those 10 foot dishes weigh? I know with everyone turning to small satellite dishes the large black mesh dishes that were made for the analog C or the Ku bands are a dime a dozen.
The wind loading for the six rotators in the article run from 10 to 25 square feet. I have a huge yagi tri-bander that only runs 11 square feet of wind loading. It's boom is 24 feet long and four inches in diameter and the longest element is 28 feet. I did break the shear-pin in a 90mph canyon wind but as long as only one axis of rotation is needed then I'm sure that these rotators would work.
I've seen the printouts from Dale's RT work and it's amazing.
You mention noise rejection but spousal rejection is much more serious... B)
I can get you the QST article if you need it Dale, you've got my home email.
73 de n7zi Gary
"Why buy something for ten bucks when you can make it for a hundred." JR