Elliptical dishes are normally skewed, skewing the LNBF and also aligning the width of the dish with satellite arc. Thinking the 'theory' is an elliptical has the adjacent satellite rejection equivalent to a 'normal' offset with the same width as the elliptical. So if an elliptical is used on 103W and it's skewed 26° CW of where it would be normally, resulting in the long axis of the elliptical dish being not 'inline' with the satellite arc, wouldn't one loose adjacent satellite rejection??
Another 'elliptical' question -
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Interesting question! My thinking would be that the answer would be no, it wouldn't loose adjacent satellite rejection. In fact, since both horizontal and vertical transponders of adjacent satellites would off by approximately 26 degrees (sort of in the middle of horizontal vs. vertical placement) any interference would be even less. But that would also be true on a circular dish. However, if you wanted to add extra LNBs on an elliptical dish skewed that much, then you'd have problems!
just my opinion
I wouldn't put an elliptical on that bird ...
The elliptical feedhorn needs to be square with the dish.
And the dish needs to be skewed to the satellite orbital location relative to your position.
If you put a round feed horn on an elliptical dish (not optimum)...
then I would still skew the dish to the orbital location (as above)
and further skew the LNBF to the strange bird (26 degrees more).
I wouldn't put an elliptical on that bird ...
The elliptical feedhorn needs to be square with the dish.
And the dish needs to be skewed to the satellite orbital location relative to your position.
If you put a round feed horn on an elliptical dish (not optimum)...
then I would still skew the dish to the orbital location (as above)
and further skew the LNBF to the strange bird (26 degrees more).
elliptical addendum
Lately, we've had a lot of discussion about DishNet band stacked LNBs and Feedhorns on DirecTV Slimline dishes.
As a result, that limited my thinking.
There is no provision with those LNBs and feedhorns to attach 'em together any way but "square".
The two pieces bolt together just one way.
So, if the feedhorn is square to the dish (mandatory) the LNB will be, too.
There is another dish without that limitation.
I'm thinking of the Primestar 84e.
The feedhorn is fixed to the LNB support arm, and square with the dish.
However, the LNB can be rotated independently!
Should make an ideal solution
Lately, we've had a lot of discussion about DishNet band stacked LNBs and Feedhorns on DirecTV Slimline dishes.
As a result, that limited my thinking.
There is no provision with those LNBs and feedhorns to attach 'em together any way but "square".
The two pieces bolt together just one way.
So, if the feedhorn is square to the dish (mandatory) the LNB will be, too.
There is another dish without that limitation.
I'm thinking of the Primestar 84e.
The feedhorn is fixed to the LNB support arm, and square with the dish.
However, the LNB can be rotated independently!
Should make an ideal solution
Applying pure logic to your premises and conclusion, the answer is no. There is nothing to support such a conclusion. Applying science, I agree with Keith. If your receptor for verticle and horizontal signals are out of sinc with the neighboring statellite signals, there should be less cross-over compared to using the dish for another satelite. There should be equivalent cross-over as a round dish used for the same satellite..
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Well, I would say that for maximum adjacent satellite rejection, the dish must be skewed.
To not skew to the arc is to not use the full width of the dish as intended.
So, I'm going to have to answer: yes.
Of course with round dishes and intermediate values of skew, mounting the dish vertical is fine.
To not skew to the arc is to not use the full width of the dish as intended.
So, I'm going to have to answer: yes.
Of course with round dishes and intermediate values of skew, mounting the dish vertical is fine.
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