OTHER General LNB(F) with motor/rotor question

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jessica6

SatelliteGuys Family
Original poster
Nov 21, 2021
50
36
Tucson, AZ
I'm still not very clear on something: If I were to get a motor for my dish, how does it deal with the LNB rotation? I was thinking maybe the motor rotated the LNB while it moved the dish from east/west, but not sure. If that's the case, is it a valid statement that the LNB would be set to 0 rotation if I were to be hitting a theoretical satellite directly south ? (in my case, 110.84 °W ) And my LNB would always be set to zero; the dish itself would rotate clockwise/counterclockwise to effectively rotate the LNB?
 
I'm still not very clear on something: If I were to get a motor for my dish, how does it deal with the LNB rotation? I was thinking maybe the motor rotated the LNB while it moved the dish from east/west, but not sure. If that's the case, is it a valid statement that the LNB would be set to 0 rotation if I were to be hitting a theoretical satellite directly south ? (in my case, 110.84 °W ) And my LNB would always be set to zero; the dish itself would rotate clockwise/counterclockwise to effectively rotate the LNB?
Yes, that is correct. Your lnbf is set to zero with dish at true south and as the dish turns/tilts to the left or right the skew is taken care of automatically. :)
 
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Yes, that is correct. Your lnbf is set to zero with dish at true south and as the dish turns/tilts to the left or right the skew is taken care of automatically. :)
Thank you! This is the piece I was missing. I found a picture online which kinda helped me reason it out a little, too. That's really cool.
 
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Just like my broomstick demo. Once you're out of the azimuth/elevation way of thinking and into polar mount tech it all becomes clear. Consider mounting a dish on a telescope mount, setting your angles. Ba-da-bing!
Merry Christmas.

1640290346032.png
 
When I noticed the name on your scope I said several things I can't repeat on the forum...
 
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Thanks for all the great responses!
Sorry, Arlo! I didn't quite understand the broom example you provided me a few weeks ago. But I think it makes more sense now.

If I were to get a motor, what would be a good choice? On my receiver, I have some options in my setup:
DiSEqC1.0 Disable
DiSEqC1.1 Disable

Motor Setup: [ NONE | DiSEqC1.2 | USALS ]

I found this one:
HH90 USALS | Satellite Antenna Rotor - Stab

STAB HH90 DiSEqC Horizon To Horizon HH USALS Motor NEW

Also, regarding my LNB angle, it looks like I pretty much got it aimed right at the center of the pentagon mounting screws displayed in the following image. Isn't that where it should be pointed?
20211223_151958.jpg


Thanks again!
 
Just like my broomstick demo. Once you're out of the azimuth/elevation way of thinking and into polar mount tech it all becomes clear. Consider mounting a dish on a telescope mount, setting your angles. Ba-da-bing!
Merry Christmas.

View attachment 155152
Just like my broomstick demo. Once you're out of the azimuth/elevation way of thinking and into polar mount tech it all becomes clear. Consider mounting a dish on a telescope mount, setting your angles. Ba-da-bing!
Merry Christmas.

View attachment 155152

Verrrry nice scope. Moonlite focuser ? Compared to yours my less expensive 4" Stellarvue sits on an Orion Atlas EQ-G mount. Happy viewing !!!
 
Thanks for all the great responses!
Sorry, Arlo! I didn't quite understand the broom example you provided me a few weeks ago. But I think it makes more sense now.

If I were to get a motor, what would be a good choice? On my receiver, I have some options in my setup:
DiSEqC1.0 Disable
DiSEqC1.1 Disable

Motor Setup: [ NONE | DiSEqC1.2 | USALS ]

I found this one:
HH90 USALS | Satellite Antenna Rotor - Stab

STAB HH90 DiSEqC Horizon To Horizon HH USALS Motor NEW

Also, regarding my LNB angle, it looks like I pretty much got it aimed right at the center of the pentagon mounting screws displayed in the following image. Isn't that where it should be pointed?
View attachment 155155

Thanks again!
No problem. Skew isn't that hard to understand. If you stand facing south with your arm out 45 degrees. palm flat and thumb facing up. Trace an imaginary arc up and over your forehead. Ending up with your arm on your right side. Palm will be flat, straight up and down and your thumb will point to the dirt..
Palm should be flat in front of your eyes when...it's in front of your eyes! Right? That's skew-moray.
 

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Also, regarding my LNB angle, it looks like I pretty much got it aimed right at the center of the pentagon mounting screws displayed in the following image. Isn't that where it should be pointed?

No. It should normally be pointed even a bit lower than the deepest point of the dish, for an offset dish that isn't mounted upside down.

Some say it is best to point it at the so-called G-spot of the dish (at the end of the line, bisecting the top of the dish to LNB line and the bottom of the dish to LNB line). But a little bit higher might even be a bit better, signalwise.
So if it is pointing somewhere between G-spot and deepest point, I would be happy.
In that zone, the exact pointing is not quintessential anymore, I believe.

Greetz,
A33


BTW. I'm losing track a bit of the many topics you started, about just one satellite setup. The information, questions and answers are spread out over multiple topics, now. I would prefer that you would stick to just one topic, to keep better track of what is going on.

And that might be more informative for later readers, that want to do the same; as all information is then in one thread.
Just a suggestion...
 
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No. It should normally be pointed even a bit lower than the deepest point of the dish, for an offset dish that isn't mounted upside down.
So my LNB needs to be pointing lower? I'm confused. In one of my other threads (sorry) someone posted a picture that it should be pointing higher:
 
No.
I wrote: a bit lower than the deepest point.

From the center of the dish, gowing lower,
you first encounter the 'deepest point',
and then a bit lower: the G-spot,
and of course, at the end, the bottom of the dish.

It is easy to see when you look at the linked post here: OTHER - Question about LNB position

Ah! When you are not a member there, you just get to see the thumbnail, not the whole picture.
The picture is also here: Type schotel? Correcte LNB houder gezocht
Or direct link to the picture: www.sat4all.com/forums/uploads/monthly_2020_09/843091569_A33OffsetsatellitedishspecscalculatorPictureoftherelevantpoints.png.50a7a86428a6eacbd1d429c94e4a2117.png


Greetz,
A33
 
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