alignment issues

[gabshere]

checking #

 

[FaT Air]

So I added the 48.65 to 6.48 for a total of 55.13 declination to set on the dish face or back across the ring.

Polar elevation at 48 lat = 90-48 = 42 degrees
dish elevation = polar elevation 42 minus declination 6.5 = 35.5 degrees
total declination is 6.5, Declination is the difference between polar elevation and the dish look angle. The above uses the horizon as zero reference.
I rounded the numbers for my convenience, change as required.

 

[jaray]

Lak7 and I took over the chat window for a short bit last night on the SatTalk radio show discussing my issue. His last suggestion was to eye-ball the declination and set it to zero.
(This would be roughly parallel with my polar axis elevation bracket.)
Then adjust elevation (which needed to be down in my case) until I saw signal and peak. From there, move it up 6.4 degrees (declination #) then lower the actual declination until signal came back and peak it.
Well, THIS WORKED! Needs some fine tuning but I can now get over to 133W.

I needed to adjust the declination up a little as I started to head towards the 133 area to get good signals. The only thing now is I adjusted just enough up to get the westerly birds, that I've almost killed SQ on my true south (89) and east.
So I'm not sure how to fix that one but I know I may have to consult those guides for over and under shooting and what scenario to follow, but this is awesome.
Everyone's help was great. I'll report back with my actual measured #'s later on for interest to see how close they are to the charted specs.

 

[phlatwound]

Good for you, jaray, glad to hear you are making progress.

Lak is a pretty smart feller, he, along with several others have got me on the right path many a time, this is a great forum. :up

 

[FaT Air]

Start over at true south. Then when you go to 133, try peaking Q there by rotating the mount on the pole ever so slightly one way or the other. Do not adjust declination or elevation. The elevation will be fine tuned by the actuator on the end of the arc. Mark pole/mount location, Then check center and the other side of the arc. If you have to rotate the mount to get this side of the arc. Check location of the mark on the pole. Adjust mount to the midpoint between these marks. Go to center sat and adjust declination for peak and repeat the ends of the arc. Should Be very close.

 

[IdahoBill]

Hi
One thing to look for is the focus dimension. Check your dish manual for this number. I find thar the horn keeps sliding toward the hub when the wind blows. I put a stick from hub to base of LNB to stop it--workss good.

IdahoBill (still trying to figure out this site)

 

[Lak7]

Scroll down to the "Philosophy Chart"
Footprints by Dish Size - Adjusting the Polar Mount for Prime Focus Antenna - C/Ku-Band Satellite Systems - Tuning, Tracking, Azimuth, Elevation, Declination Angles, F/D Ratio, Focal Distance, Inclinometer, LNB/Feedhorn Assembly, Actuator Assembly, C
What you want to do is adjust your Azimuth so that the East and West ends need the Same Adjustment - both ends are too high, or too low.
Once that is done, you start to fine tune.

 

[jaray]

So I peaked my true south after setting correct elev/declination. (good signal)
From here, I headed over to 133 and had no signal at all to peak.
If I had signal at 133 to peak then yes, I would likely need to rotate the mount a little one way or the other but in this case there is no signal to peak. I only start getting the signal if I raise the dish a couple degrees. If I do this then again I lose 89. It seems there's no happy medium and I know I have signal to gain.
It seems I can get my high sats, but then not the low westerly ones, or vice versa.

Start over at true south. Then when you go to 133, try peaking Q there by rotating the mount on the pole ever so slightly one way or the other. Do not adjust declination or elevation. The elevation will be fine tuned by the actuator on the end of the arc. Mark pole/mount location, Then check center and the other side of the arc. If you have to rotate the mount to get this side of the arc. Check location of the mark on the pole. Adjust mount to the midpoint between these marks. Go to center sat and adjust declination for peak and repeat the ends of the arc. Should Be very close.

 

[stanleyjohn]

I went through the exact same problems as you are now seeing and for me it was rechecking everything and finding that my declination,elevation,miss aligned LNB and a slightly uneven mounting mast were my problems.I would start by seeing how far off i was now then go from there!How much of the arc can you see now?Mark everything!with some masking tape so when you start moving things again if things get worse instead of better you can go back to where you started.Take your time! for me it took weeks before i finally got it right.Your at the right place for help and info!alot of great guys and gals here. What FaT and others have said about going between your true south and the western most sat is good info.In your case u may need to cheat alittle because your not getting your farthest west sat.Find one alittle father east if you can and work with that in your adjustments!just dont tweak it as much as if you had the farthest west sat.Hope this helps! Been there and done that!! Stan

 

[Lak7]

It seems I can get my high sats, but then not the low westerly ones, or vice versa.

Don't try for the extreme Ends first, start at your True South Sat and work your way East and West, say 10 degrees each way. Make notes of which are side is too high / low, and adjust the mount's Azimuth.
Once both sides are the same - high or low, you would then adjust Declination

 

[jaray]

I find most of the satellites from my 89 true south heading west, do have good signal and don't need any peaking. Its not until i get to the further reaches (131, 133) that signal is almost gone. Perseverance is key I guess...

 

[stanleyjohn]

It looks like only a small adjustment will be needed! How about when going east from the center! does the arc track well on those sats?

 

[jaray]

My 18" actuator only gets me to 72, so I haven't really got too concerned with easterly, but I know i had to make an adjustment to get it...I'll have to check on that again...

 

[sonyajon]

One more alignment question

We have been following this thread and have found it to be extremely helpful.

Thanks to everyone.

The one question we have, is it seems that your supposed to set your declination angle first and leave it be and then set the polar elevation.

Where should the polar mount be - when you set the declination angle? Or does it matter.

Problem we have is the Polar Elevation is supposed to be 57 for us and the declination should be 52. On a SAMI 10 ft, this is hard to do since we are out of threads on the adjustment rod

Here's where we are

Elevation = 32.60 degrees
Declination is 4.66

90 minus 32 = 57.4 (Polar elevation)
Polar Elevation of 57.4 minus 4.66 (Declination) = 52.74 Declination Angle
We are putting our angle finder on the round plate on the back of the dish

Maybe we have missed something in the interpretation, any help would greatly be appreciated, Thank you

 

[jaray]

FYI...all I was doing wrong was using the angle finder the wrong way. Well, either I had to minus by 90, or simply flip my inclinometer over. So I flipped it over while measuring the declination and was now measuring the correct number. (which in my case was supposed to be 34.5 (and NOT 50 something, no wonder why I couldn't push the dish up enough to achieve the number I thought I needed to)

 

[Lak7]

To me, it does not matter which is set first.
But when you say you are running out of space for declination, that doesn't seem good.
Here is a good site for Polar Mount angles...
Satellite finder, how to point dish with magnetic north, azimuth and elevation program calculator.
Try setting the Declination adjustment so that it's centered on the threads, is it about parallel to the Mount Ring?
If so, just use the Elevation Adjustment to find / peak the signal on you True South Sat. Use the Elevation Adjustment to Raise the Dish the amount of you Declination, then use the Declination Adjustment to Lower the Dish back to peak signal.

 

[FaT Air]

No you're not missing anything I can see, But remember that using the 90 minus (whatever number) is for when you are changing your ZERO degree reference. One set of numbers use the vertical as zero, the other set is the horizon. Generally speaking I find it easier to understand if Elevation angles reference the horizon as zero. Easy way to see what is referenced is to hold angle finders used face horizontal, needle is at 0 or 90, then watch it go thru 10, 20, 30(for 0 horizon reference) or 80, 70, 60(for vertical 0 reference) until it is at angle being measured When one mixes numbers using two references is usually where the confusion occurs.

 

[sonyajon]

We finally got it, and today we got it all. East West and South. Thank to everyone who helped us, we REALLY APPRECIATE it

 

[LocutusOfBorg]

I've been struggling for some time thinking that my aiming on my 6' mesh was not quite right.

I am sitting at my true south (89). I set my polar axis elev to 48 (which is my latitude for my area)
At this point I lose signal, then I pull the bottom of the dish inward using the declination bolt and start to see signal come back. I peak using this declination and see descent signal.

This is where the problem starts, when I measure where my dish is facing now that I've supposedly dialed in declination, I am at about 35. So do the math and it equals about 13 declination. My declination is supposed to be 7, not 13. If I change the declination to an angle of 41 (48 minus 7) all signal is gone.

Is there something grossly wrong with my logic here?

Footprints by Dish Size - Adjusting the Polar Mount for Prime Focus Antenna - C/Ku-Band Satellite Systems - Tuning, Tracking, Azimuth, Elevation, Declination Angles, F/D Ratio, Focal Distance, Inclinometer, LNB/Feedhorn Assembly, Actuator Assembly, C

 

[Cham]

When I originally set up my first C-band dish I would align the polar axis at night with a clear sky and line it up with the north star. Then I set the declination to peak the southern most satellite. Works well but not perfect, there are variations due to the pole and mount flexing while the dish moves along the arc, and I find using a bit less declination (than the charts) seemed to improve the east and west most satellites. My current dish is really heavy so this might not usually be an issue..
Also, the more you have to work setting it up now will give you good experience for the future, and you'll enjoy your dish that much more!
-C.