[amsat-bb] Re: Limits of G-5500?

[Edward Cole]

At 05:25 AM 3/7/2009, Mark L. Hammond wrote:
>Hi All,
>
>Recently I acquired a 7.5' dish.  It's aluminum with a steel ring 
>mount.  I estimate the dish weights maybe 50 lbs?
>
>What is a realistic limit for a Yaesu G-5500 rotator?  Would it 
>handle a dish of this size/weight if carefully counterbalanced?  Or 
>is it too big and silly to even consider?
>
>I know wind load is a concern of course, too.  But I imagine keeping 
>it close to the ground...
>
>I've thought about cutting it down in size to reduce weight and wind 
>load, but would rather not go that route...
>
>73,
>
>Mark L. Hammond  [N8MH]

Mark,

Is the G-5500 the same as the B5500?  I would not recommend 
that.  The issue is not the weight but the wind area forces.  A 7.5 
foot dish can have 2000-lbs of wind force at 70mph.  What is 
recommended is a HD azimuth rotator coupled with a satellite dish 
actuator arm for elevation.  I do this with my 2m-eme array (four 
21-foot booms on a 12x12 foot H-frame).  The B5500/B5400 will handle 
up to a 3-foot dish probably at maximum.  I have had a 33-inch offset 
feed dish on my B5400 along with a long 432 and 1296 yagis with no 
problems (knock on wood).

Satellite actuators are pretty cheap for running a dish.

73, Ed - KL7UW