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Re: receiving system design tradeoffs



>  A smaller dish is more likely to be suitable for a Yaesu az-el rotor, and 
>doesn't require as elaborate a mounting structure.

And herein lies one of the real problems we face, that the Yaesu rotors are 
really too light duty to do what they are supposed to do.
Again, I have one, and I paid $525 for new (which was a screaming deal).  
Again, $75 TVRO actuators beat the pants off of the Yaesus.

I'll end up using that rotor at least initially since it's easier to do.  
But man,  it is weakly built to be as expensive as it is...but I think
a 3' offset would work if you limited the max operating windspeed, balanced 
it well, and pointed the system straight up when not using it.

Your 23" G3RUH is at least a 6dB better setup than a BBQ, so my point still 
remains here.  It's a money versus time versus mechanics
issue.  I can tell you one thing: moving from Chicago (actually Grayslake, 
IL very close to you) to Iowa greatly increased the
wind design requirements for all my antennas.  I don't think many people 
understand how windy the plains are!!!  But then again
ten foot dishes here survive for years with the better mechanics of the dish 
actuator arms.  So it's possible to design systems that have better
mechanics for less money than the Yaesus...(Buildings here have to be 90 MPH 
rated versus 80 MPH in the Chicago suburbs, with higher requirements for 
snow load)

So I'm painfully aware of the tradeoffs.  It is true that everyone should be 
running a preamp unless that preamp is built into the converter.
I usually build mine, so its a $50 preamp for me rather than $120, but to 
each their own.
>
>My home AO40 receiving setup is a 23 inch diameter G3RUH dish, G3RUH patch 
>feed, DEM preamp (0.7 dB NF), and a cheap TSI downconverter.  The dish and 
>10-foot VHF/UHF yagis are on a roof tripod with a G-5500 rotor.  A 3-foot 
>dish would overload my rotors and force me to upgrade the mounting 
>structure.
>
>Wayne Estes W9AE
>Mundelein, IL, USA
>
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