Hitting 97W

Status
Please reply by conversation.

cliffhanger31

Well-Known SatelliteGuys Member
Original poster
Aug 2, 2009
25
0
Arizona
I have set up my own dish with motor and it works great. Now am trying to set up a stationary dish for my mother in law but can't seem to get 97W dialed in. I have the dish mounted to two pieces of plywood, anchored down with the cross beams the mounting system came with and the plywood weighed down with eight concrete blocks. The mounting post came with a leveling bead to ensure it was straight up. My idea (question) is about skew or circular rotation of the dish. On my motorized system, the motor's post dealt with getting the correct skew. However, on this stationary dish, there is no facility to adjust the skew. The LBN can be twisted from - 20 to + 20 (markings on the housing for the LBN) which I am guessing could accomplish the skew setting. Is this correct ? For Tucson, Arizona the skew value is - 20.5 I believe. Any input would be appreciated and other things I should check. Thank you.
 
If the dish is fixed you skew the LNB by twisting it

If you are standing in front of the dish facing it, the skew would be turned COUNTERCLOCKWISE 20 degrees

A motorized system figures in skew when the dish moves across the arc :)
 
That's okay, I always give directions from behind the dish!
Seems more natural to me, but apparently not to anyone else.!. - :D

This GeoSat web site will keep you honest.
Put in your country, state, city, then select the closest zip code...
...click the blue tab that says Full Satellite List...
... scroll down to 97° and click on it...
At the bottom of the page, you'll see your aiming and twisting info, for that satellite.
 
That's okay, I always give directions from behind the dish!
Seems more natural to me, but apparently not to anyone else.!. - :D

This GeoSat web site will keep you honest.
Put in your country, state, city, then select the closest zip code...
...click the blue tab that says Full Satellite List...
... scroll down to 97° and click on it...
At the bottom of the page, you'll see your aiming and twisting info, for that satellite.

Awesome site, thanks!
 
"That's okay, I always give directions from behind the dish!
Seems more natural to me, but apparently not to anyone else.!."

Me, too, Lizard. I always emulate the lnbf movement, with my hand, as I envision the motorized dish turning either east or west , and get the direction of lnbf skew from that mental image.
:)
 
Ok, changed the skew to the correct setting. I am using a $12 satellite signal meter and moving the satellite in any direction, reduces the signal strength. It now shows 99% signal strength and zero signal quality. Other things I shoud be checking such as all remaining settings associated with 97W????? Thanks in advance.
 
Ok, changed the skew to the correct setting. I am using a $12 satellite signal meter and moving the satellite in any direction, reduces the signal strength. It now shows 99% signal strength and zero signal quality. Other things I shoud be checking such as all remaining settings associated with 97W????? Thanks in advance.

Remove the Satellite signal meter and see if you got quality.If not than slowly move the dish east or west. I have a cheap meter and it was droping my quality about 30% or so. Good Luck
 
Ok, changed the skew to the correct setting. I am using a $12 satellite signal meter and moving the satellite in any direction, reduces the signal strength. It now shows 99% signal strength and zero signal quality. Other things I shoud be checking such as all remaining settings associated with 97W????? Thanks in advance.

I found my cheap-o analog meter to be pretty useless. I could find a signal, but there are so many up there it was impossible to dial in on the right one. I take out a receiver and a monitor from a portable dvd player. I set my receiver to a known transponder and then I set my elevation on the dish and sweep it from left to right (or vice versa). If I don't get a signal, I move the dish up or down *very slightly* and repeat. Once I get a little signal, it's the usual tweaking from there.
I haven't used my analog meter since the day I found my first signal. It's just a (literal) headache.
 
LNBF Polarity or Dish Skew

The easiest way to remember the direction you need to rotate your LNBF to polarize it correctly is to know the longitude coordinate of your site and the orbital degree position of the satellite.

If the orbital degree of the satellite is further EAST than your site's LONGITUDE position, rotate the LNBF so that the TOP of the LNBF is turned towards the satellite or to the EAST.

This way, it doesn't matter if you stand in front or behind the dish as the top of the LNBF still turns to the same direction, which is towards the satellite. Then you won't be confused as to whether the direction should be CW or CCW based upon your reference point (front or back of the dish).

I have always imagined a rainbow in the sky that is directly to my south and aligned with the equator. Then, I draw short lines (in my mind) which are tangent to the circumference or the outer perimeter of that rainbow and a short perpendicular line to those tangent lines to make a "cross" or "tee" in the sky. Next, I think of my LNBF as a gunscope with a "tee" crosshair in the center of the boresite. If I aim that gun scope at the satellite that I want, I have to twist the scope CW or CCW in order to align the crosshairs in the scope with that "tee" in the sky so that the horizontal and the vertical lines align up between the two.

I find it really quite simple to visualize it all this way. You are simply using a bit of geometry and tangent lines to a portion of an arc of a circle and a bit of hunting expertise. It allows me to envision what I really cannot see with the naked eye.

This all makes it much simpler to remember as you can understand the theory, instead of a memorized rule.

This works the same way with a multiple circular, LNBF dish (such as DishNetwork's DISH 1000) where you do not polarize the LNBF itself, but where you SKEW the dish. Just remember that in both instances that you rotate the top of the LNBF or the top of the dish towards the satellite (or satellites).

Consider my old DN DISH 1000, which had LNBFs for satellites 110°W, 119°W and 129°W and my site's longitude coordinate which is ~97°W. In this case, all the satellites are west of 97 degrees so the entire dish is rotated (or skewed) towards the west. In other words, the dish was rotated so that the top of the dish rotated to the west. The entire dish itself is most closely aligned as if 119°W was the primary satellite at dead center (since 119 is nearly dead center between 110 and 129, with a little fudge factor).

RADAR

P.S. There is one satellite that is a little messed up in this regard. But, I will leave that for another discussion.
 
Status
Please reply by conversation.
***

Users Who Are Viewing This Thread (Total: 1, Members: 0, Guests: 1)

Who Read This Thread (Total Members: 1)