Declination ?/Problem

**Long Hair** · 10-06-2009 09:34 PM

I was adjusting my declination and noticed that my elevation moved as well. Is this a problem

**johnnynobody** · 10-06-2009 10:06 PM

Originally Posted by Long Hair

I was adjusting my declination and noticed that my elevation moved as well. Is this a problem

Changing declination will affect your ability to accurately traverse the arc. For peak performance you'll need to fine tune the dish.

**Long Hair** · 10-06-2009 10:58 PM

Originally Posted by johnnynobody

Changing declination will affect your ability to accurately traverse the arc. For peak performance you'll need to fine tune the dish.

the reason I adjusted the declination was to fine tune, than I checked the elevation and it moved as well. So again I ask should my elevation move when setting the declination? My elevation should be 39.60, after setting my declination 5 degrees. My elevation moved to 41, it should stay at 39.60 right?

**Anole** · 10-07-2009 01:35 AM

The two interact.
So, get solidly on a satellite,
Then you measure and change the declination a little,
That screws up your elevation, so you adjust only the elevation to bring you back onto the bird.
Then, you can run the arc again to see how well you track.

This is only one component of a comprehensive retracking, but it answers the question asked.
For a fuller discussion, I'd refer you to the
GeoOrbit

site.
Near the bottom of that page is a graphic which should help you understand what to do, depending on your tracking error.

Here on the site is more
info on declination

.
The chart at the bottom of this page is the only one I'd ever use:
Modified Polar Mount Tracking Angles

edit:
In a perfect world, you measure and set your declination ONCE, and leave it alone!
Only if you see a tracking error as described above, might you consider changing it.

**Lak7** · 10-07-2009 05:50 AM

Is this on a BUD?
If so, changing the Declination angle should not change the Main Axis Elevation, you should only see a change on the Face of the Dish.

**Long Hair** · 10-07-2009 07:15 AM

Originally Posted by Lak7

Is this on a BUD?
If so, changing the Declination angle should not change the Main Axis Elevation, you should only see a change on the Face of the Dish.

Lak this is a 7.5 unimesh bud. And that is what I thought,I think if my elevation is changing than the bolt for the elevation might be lose where it bolts up the the mount causing it to slip just a bit. At one time about a week ago I think I had my declination set close because I was able to pick up ku band, but now only c band.
I'm sure my declination is off because on sat w5 on hbo 4dtv h= 89quality and v=58 quality. It makes no real difference if I adjust my skew. I'll post a pic showing what I think my problem is.

**Lak7** · 10-07-2009 08:44 AM

That is the same mount I have.
Make sure everything is tight. Check the 2 Nuts with the Cotter Pins.

Get everything tight, then set the Main Axis to your proper setting. I found no "prefect" place to measure Declination on that mount.
I found the most important thing is the Azimuth, use every trick in the book to get the Azimuth correct.
I set the Azimuth to the actual Main Axis Square Tube, then set the Main Axis Elevation.

**Long Hair** · 10-07-2009 05:07 PM

[quote=Lak7;1980924] I found no "prefect" place to measure Declination on that mount.

yeah I noticed that, I measure declination from the front center plate. Unless someone thinks this is a bad idea?

**Lak7** · 10-07-2009 06:15 PM

Nope, ut that's a good starting point.
Just make notes when tweaking, keeps ya from going crazy.....

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

**PANHANDLER** · 10-07-2009 06:51 PM

I have the same mout and it drove me crazy trying to track the belt . I was trying to set the declination from the same point ( the plate) but after several attemps still couldn't quite get it. What i did was use a straight edge ( 1/2" x 2" aluminum bar ) and put it rite on the rim of the dish ( on the face ) and there it was , i am now able to track the entire belt.