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Re: BBQ Dish Sanity - more info




>At 11:34 AM 8/14/03 -0800, Edward R. Cole wrote:
>
>>Hi Guys,
>>
>>Good luck on this.  Let me mention that I have both 39-inch and 33-inch
>>offset feed dishes above my roof that have withstood 65 mph sustained winds
>>for a 30-hour period this spring.  The 33-inch dish is mounted on a G5400
>>with aluminum crossboom.  The clamps did slip so the dish is looking
>>downward but is easily reset (no damage).

Hi Tony, Ed, interested others,

I took some pics with a short narrative at:

http://home.san.rr.com/doguimont/uploads

p8t.jpg, p101t.jpg, p14t.jpg with primestar.txt to describe...just click to 
view..

I don't know why anyone would be hesitant about mounting a Primestar dish 
on a G5400 rotor system...  I've used an ~18 year old one that has seen 
about that many FD's in addition to lots of low orbit cw, digital, ssb use.

I used it for all the low orbits, A010, AO13, (dish on mode L), and now a 
dish from the first day AO40 xponder has been on, and it is still functioning!!

The pics show the mounting device, homebrew, with added "tail 
counterbalance weights" to maintain a positive "nose up" configuration at 
all ELs..I removes the EL rotor slop, and at the age of my rotor there is 
plenty of that!  A new system will probably not require the counterbalance, 
thereby reducing the weight and associated torque.  With no counterbalnce 
the "neutral" position is about 40°.....The Primestar is mounted with the 
feed arm on top, and with the 1 1/4" spacing to the boss on the EL rotor.

I think a portion of the 27 EL homebrew circular 1.2 yagi (built for O13) 
is visible in one of the photos.  Usable with a barefoot ICOM 910 at low 
squints using the counterbalance to improve dish accuracy on mode L at 
higher squints..

All is mounted on a push-up mast with a 1 1/4" glavanized mast top section.

I can "strong arm" the slop in the rotor at ANY EL, using the 1 1/2" 
horizontal support and I'm 81 years old!
I'm sure that indicates much less than the 102 ft-# spec...

My 5400 is rated at 102 ft-lbs EL with a windload of 8.5 square feet.  If 
we get our infrequent 40 knot winds in San Diego (about once every 5 years) 
I simply park it in the near horizontal plane..  that is much less than the 
rated windload.  I have no idea of how the windload is rated!

The horizontal torque is negligible in comparison the lever arm provided by 
large beams.

The whole affair fits easily in my standard Ford sedan for a trip to any 
site reachable by road...

I think there are places that are still giving away PRIMESTAR dishes...I 
HAVE NO SOURCE!!



            73, Dave wb6llo@amsat.org
                    Disagree: I learn....  


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